$3M portfolio - how to balance long term growth and preservation during downturn

Mid-30s. SINK. Portfolio just crossed $3M with ~50% in VOO, 30% VGT, and 20% individual tech stocks (Nvidia, Microsoft, Google). Also has a rental property I’m hoping to sell this year that would net about 150k cash.

I’m really hoping to FIRE by 40, and maybe take on the family business. How should I think about rebalancing or proofing my portfolio so that it maintains growth but also can also preserve during a period of downturn?

I was thinking maybe keep the 150k cash proceed in SGOV, and slowly get my portfolio to 70% VOO and 30% VGT.