I'm about your age (34) and understand feeling the need to save as much as possible. I was maxing out my Roth IRA when I was making <$25k an year (grad school). Once I graduated and started making "real" money, I was saving probably 25%-30% of my gross income for about 3 or 4 years, although I never maxed out a 401(k). But a couple of years ago I started really thinking about what I really wanted. I like some aspects of FIRE, but I don't want to sacrifice all of "now" for it, especially since I mostly enjoy my work (indeed, I think my "ideal retirement" would still involve working part time). I got married, bought a house, and plan to start a family soon, so there's financial obligations that I had to address.
So I started looking at my account balances and some simple projections of their value at retirement and started to realize that I was actually in pretty good shape, even if I made conservative estimates. I reevaluated my savings and decided to keep maxing out the HSA but I dropped the 401(k) down to just get the full company match. I still add to the IRA and often max it out, but it isn't a huge priority. I'm now saving around just12-15%. And I feel ok with that because I already have a good foundation. I would feel very differently if I were just starting my savings journey.
Obviously, what level of savings that make you sleep at night is very personal, but you sound like you probably have more saved up that I ever did, and I have saved up much more than most at our age (not really a great indicator, of course). Look at what you have and what you want and reanalyze if what you're doing is getting you there. Personal finance isn't about running up the score before the end of the game (you can't take it with you, after all), but it's about being able to comfortably enjoy life the best you can.
And with regards to the house, this is going to sound sacrilegious, but you don't need to have 20% down. Yes, you'll have PMI costs that you'll have to factor in. You'll never get the money back that you spend on PMI, but the same is true on rent, or interest. We only put down about 7% on our home 3.5 years ago (again, not unlike you, we put a lot into the retirement) and had to pay PMI. For us, it was worth it. It wasn't that much more in the scheme of things, and since we went with a 15-year loan we were able to get it removed in 2.5 years. If we waited to save up 20%, we might still be saving and would have spent much more on rent than on PMI. The calculation will most assuredly be different for you (our house was just over $150k, not $300k, and PMI was ~$40/month, so basically an temporary extra 0.25% on the interest). But it's a calculation that you should look into doing.