What am I missing?

I won't play coy and ask if I'm "doing OK" — I know I am! I just want to see if anyone has advice that I might have overlooked.

My partner and I are in our early 30s. No kids yet, but planning on it soon. High cost area and we love it so we aren't moving.

• 401ks: $550k
• Roth IRAs: $135k
• HSA: $8550 (just opened this year)
• Taxable brokerage accounts: $1.1m
• Emergency fund: $35k (in a 3.5% HYSA)
• Plus some shares in a startup I used to work at, worth ~$200k right now but it's not liquid

Only debt is our old house which we don't live in right now while I'm in school, and we're currently trying to sell:

• $900k sale price, we put $400k down.
• 2.9% COVID-era interest rate

Currently my partner earns $200k at a tech firm and I earn about $35k as a student. I took a few years off from big tech to get my PhD. Before my PhD I was earning $300k. Next year I'll graduate and go back to the tech industry, hopefully with at least a similar salar. Once I graduate we plan to buy a bigger house and have kids. I modeled a safe house budget at $1.5 – 2m depending on my salary.

My partner maxes out her 401k (and I will too once I'm working again), and each year we each do a backdoor Roth contribution. We just switched health plans and plan to max the HSA.

So what should we be doing that we aren't?