Wow, congratulations - you are knocking it out of the park in savings and in spending. I wish we were so disciplined in the spending department! I'll try to answer your specific questions with the caveat that we have our own problems!
Specific Question(s):
1. I did not sell anything during the last few market downturns, and think my hefty savings account has helped me. How face-punch worthy is the amount I keep in savings?
It is over three times your annual spend, plus you have a large sum in a taxable account. I'm not sure this is face punch worthy because everyone's comfort level is their own and it is better to have the money than not, but it probably isn't necessary for emergency purposes alone. Do you have plans to buy a home one day? You said you don't have a life plan - I'd think about that and then put some of this money to work to make it happen, which might mean leaving it right where it is but also may mean something different.
2. I think I might have anxiety about spending money. I frequently have remorse and spend weeks/months thinking about any purchase over $30 pretty much. Do I live too frugally and stress the cents too much? Is my spending unreasonably low?
Only you can answer this question but related to question 3 - therapy is something that could help. I think everyone could benefit from a good therapist at one time or another.
3. I have a wish list of things to buy if money were unlimited – a backpack to try backpack camping, a hybrid bike to replace my 1970s bike, home air purifier, hiking boots, a taller vehicle to be able to drive more than 2 hours with my severe back issues, anxiety treatment/therapy, a fancy sleeping pad for camping, some nicer home furniture, music lessons, a screen tent\gazebo, adult swimming lessons to learn how (once covid is over), but none of these are essentials and I live fine without them. Now that I have the car paid off, the emotional part of me wants to start buying things on this list which I have held back on for the past few years. How do others make decisions about what to purchase beyond essentials? I worry even if I bought everything on this list, new items would appear and it would lead to a never ending cycle :(
If you want a stranger's view, here you go: Get into therapy, get swimming lessons (safety issue! also might help with back pain), get music lessons (activities makes us happier than things), get a used bike off craigslist.
Wait on the backpack, boots, sleeping pad, and screen tent until you are sure you like backpacking. Borrow or rent instead. I know a couple people who bought a whole kit in preparation for their first backpacking/camping trip, hated it, and then had this stuff just lying around. Also, going a few times before buying will let you know what you really need - e.g., many people recommend backpacking in lightweight tennis shoes instead of boots now. (P.s., I recently joined a statewide LGBT hiking/camping facebook group - gay man here - and it is full (full!) of women. Maybe look for a similar thing in your state and kill two birds with one stone??? Good luck!)
Hold off on the car, furniture, and air purifier. Won't make you happier at all. I'm a little surprised you want a new car when you seem to be so happy to have just paid off your car loan.
Right now we spend to make our life easier. We definitely do too much of that, but with a toddler in the house, a pandemic, no family support, and two full time jobs, it is worth it to us. Prior to covid, we spent discretionary funds in two ways: (1) activities/experiences, and (2) improving our living situation - big expensive house. Having done both, I agree with all the studies that say spending on activities/experiences will bring you more joy than spending on things. Even when we spend money on things (e.g., kitchen remodel, garden), the joy we get out of the spend is how we are capable of sharing the new thing with others. Our kitchen remodel made it easier to have friends over or cook big meals as a family and our garden is fun to dig around in with our son.
4. What am I missing in my financial picture? Should I have some type of disability insurance? A will or trust? A different asset allocation? A tax advisor/financial planner?
I take it your work doesn't provide disability insurance? I have it through my job and am happy to have it.
Unless you really care where your money goes after you die, as a single person with no children you likely don't need a will. If you die without a will, your assets will be distributed in accordance with the laws of intestacy of your state. Likely first to your parents but if they are dead, then to siblings, and then to siblings' children, cousins, etc. A will would get them the money faster. If you would prefer money going to a charity or to someone else, then a will could help. You may want a power of attorney (healthcare or financial) if you have thoughts on how you having a serious illness should be treated, and this is often included with a will so there is that.
I like your asset allocation.
We're considering a fee only advisor. In your case, they will likely ask you what your goals are first so probably best to start figuring that out! You're young! You've got time! Good luck!