MrSpendy is spot-on in his analysis.
Max out the deductible 401k contributions and the HSA contributions. Starting now. Your tax analysis is correct and Uncle Sam will reward you generously on your tax returns for doing so. Invest the 401k in a diversified index-fund portfolio (something like 60% U.S. equities, 20% foreign equities, 20% long-term bonds). HSAs are best held for the long term unless you are sure that have big medical bills coming soon, so invest accordingly. As others have pointed out, in an early retirement scenario there are various ways to access 401k money without penalties or excess taxes (e.g. SEPP withdrawals), so don't get hung up on the "age 59.5" concept.
Max out Roth IRA contributions each year, but for now invest it all in a short-duration bond fund. As others have pointed out, because Roth IRA contributions can be withdrawn without tax or penalty (earnings, however, cannot be so withdrawn), this is your stealth emergency / house down payment fund. You can contribute in the name of Tax Year 2017 up to mid-April 2018, so you can really make $22,000 in contributions in 2018 if you time them right. In 2019 and beyond it will be $11,000 per year.
After the above, build up a 2-3 month emergency fund in a non-tax-advantaged account. Something like an extra $10,000 in your checking account by the end of 2018.
For couples planning on having kids, I also suggest opening a 529 college savings in the name of one of the parents, and contributing each year to max out whatever state tax deduction is available -- in Oregon, that's $4,660 per year of contributions, worth 9% back (or $420 saved) on your taxes. Once the kid is born you can re-designate the beneficiary. There can be gift tax implications if you do this for many years before switching the beneficiary, but on your timeline this won't be a concern.
Put your student loans on the longest-possible repayment plan (some programs allow for 30 year terms), religiously pay the minimums as a first priority (i.e. sacrificing the above savings if you have to), and make repayments above the minimums with surplus cash flow as available (i.e. without sacrificing the above savings). The idea would be to pay this off relatively quickly -- within the next 5 years or so -- while keeping your unavoidable monthly obligations as low as possible, to minimize downside risks. Once the loan is gone, save the extra cash for a possible house purchase.
I would suggest that you avoid buying a house until your first child is safely delivered and you have a better sense of exactly what you need and when you need it. Will you stop at one child? Will you feel inspired to try for more? This may have some bearing on the size and location of the house you'd want to buy -- and you don't want to buy a house that you'd keep for less than 5 years, as a rule of thumb (to spread out the cost of brokerage fees and otherwise make it financially worthwhile relative to renting). I'd also suggest starting on baby-making promptly -- neither of you are getting any younger, and staying up all night with an infant only gets more punishing with age. The grandparents are also not getting any younger, and (speaking selfishly) they are more helpful when they are still younger and active. You are probably at the ideal time in your lives to get started.
When it comes to early retirement, I suggest having your fixed monthly expenses as low as possible before pulling the trigger, to minimize downside risk and increase stability. Given a net worth of $1,000,000, most people would sleep better with $400,000 tied up in a house they're happy living in (paid off free-and-clear and properly insured) with only $600,000 riding up and down in the investment markets, versus $1,000,000 in the markets and having to make a substantial rent or mortgage payment each month. If the market takes a dip (and sooner or later, it always takes a dip), it's easier to take a philosophical approach and not panic and sell low when all that's really at stake is whether you are flying to Paris or road-tripping to the Grand Canyon for your next big vacation, rather than worrying about the roof over your head.
Another angle to consider is whether the mother would want to go part time, or stay home, after a baby comes along. (Many people pussyfoot around and say "one of the parents" and act all surprised when it turns out to be the mother who takes time off -- I'm willing simply to acknowledge the common pattern and move on.) With a baby comes additional expense, and maintaining a two-working-parent household brings even further expense, in the form of massive day-care charges, so it's worth running the numbers when the time comes.
For your long-term outlook, I generally say that a $1,000,000 investment portfolio plus a paid-off house gives a family pretty much unlimited flexibility, assuming fundamentally reasonable spending patterns. In normal cases, nobody has to work ever again if that's what you really want, and there's a bit of spending money in the budget for hobbies that actively cost money. Similarly, a $500,000 portfolio plus a paid-off house gives you freedom -- meaning enough passive income to provide freedom from worry and freedom from having to put up with conditions that are dissatisfying. A wage should still be earned, but it can be a low as $20,000 per year or as high as you can manage, so you can pretty much pick and choose exactly what kind of job and hours are most satisfying, secure in the knowledge that your family could walk away from the income for years at a time without worry, if need be.
I'm going to divide the next 10 years into two 5 year plans:
For 2018-2022 your priorities will be: Maxing out your tax-advantaged savings accounts (detailed above), putting away a $10,000 emergency fund, paying off the student loan, having your first child (and your second, if you decide you want more), and, towards the end of that span, figuring out what house you want and buying it. The mother may drop down to half-time work at this stage when the children are young.
For 2023 to 2028, your priorities will be: Maxing out your tax-advantaged savings accounts, having your third+ child (if you decide you want that many), and aggressively paying down the mortgage. You will remain a 1 car family, and if the time comes to replace your VW (should be well past 10 years old before you think about replacement), you will buy a sensible used car as described in the blog. The mother may revert to 3/4 or full time work once the kids are in elementary school.
By the end of this ten year plan, I would guess that you'd have around $500,000 in investments (mainly in tax-advantaged accounts) and a house with a pretty big equity cushion. At this point you'll have some decisions to make: You can move to lower housing costs, and declare yourselves free -- meaning, somebody works 1/2 time to generate a bit of cashflow and possibly gain access to a better employer-sponsored health plan, but you don't strictly rely on it. Or, if you're wedded to PDX, you stay put and work relatively hard for another 3-5 years to pay down the mortgage and increase the nest egg, before calling time.
If the markets are with you, or if you have a particularly strong career move, then your numbers at the end of ten years will be better. Finding $250 in monthly savings between your food, beauty, sports & recreation, subscriptions and dining out budgets would also help a lot.
My closing point is a big-picture one: Given your stage and position in life, I would counsel against fixating on a plan for "complete FIRE" -- figuring out some savings number that will "guarantee" you the ability to live out the rest of your lives without working another day, and establishing a plan for how exactly you will get there. There are too many unknowns -- children, career path, choice of geographies, the gyrations of the stock market in the next 5 to 10 years, etc. -- to make this viable. There are huge chances that your assumptions and plans will turn out to be wildly optimistic or entirely over-conservative. The key thing is to build up your position of strength, which your post suggests you have started on well: Get a good job with growth prospects, establish good spending and saving habits, marry a good spouse, and try to avoid making too many bad mistakes. Build up good 5 and 10 year plans, and every few years evaluate your progress and status. Before you know it, you will be wealthy and spoiled for good options, including early retirement and semi-retirement, while your spendthrift friends and colleagues will still be heavily in debt and wondering how it is possible to live on less than $150,000 per year while driving everywhere in their late-model Jaguars. At this stage in life, you're goal is to deal your 38-year-old self a strong hand of cards, not write the script on the next 50 years of life.