Big picture, it looks like you are doing pretty well. You are spending about $54K/yr, so round up to $60K for retirement spending to cover extra medical costs and such, which means you need about $1.5M to cover that amount of money. You already have half of that saved, which means even if you don't save another penny, you should have enough to retire on in another decade, +/-. So my advice would be to take the time now to make sure your downside risk is covered: is your life insurance adequate to cover both of you if one of you passes (and please tell me it's a term policy)? Or, conversely, if both of you could cover your costs if one of you dies, do you even need life insurance? Do you have disability insurance? At your age, it is far more likely that you will be disabled than die, so make sure you don't need to drain your savings to cover that.
That said, I echo Freedomin5: if you'd like more specific advice, it would help if you provided more detail. Does that $4500 include the things that are taken out of your paycheck, like medical insurance? Are you maxing out your tax-sheltered accounts? Do you have an HSA option at work, or a mega backdoor Roth option?
But more than that, we need to understand your goals. Do you want to have kids? If so, do you want to have a stay-at-home parent, pay for college, etc.? Do you want to own a home, and if so how much do you project that to be? Do you want to retire immediately, are you happy working for the foreseeable future, or somewhere in-between? Your numbers are great if you want to remain DINKs with your current expenses -- but if you want to have a couple of kids, a SAHP, cover college costs, and buy a big house, that's a completely different story.