Hunters, Schlage, Parkmerced, Treasure Island are all pre-approved and you can start building phase 1 immediately at 15-20% return.
Hunter's will get hit by bad news later on, and you can take the proposal then immediately sell it for $6.4M profit on day one.
Schlage has a 2.1M permit expediter cost, if you are lucky (few RNG delays to permit/phase 1 build), then you will be able to get to 2020 and get phase 2 pencilled by optimising construction.
Mission Rock is not pre-approved but you can get to phase 1 build before the price crash in 2020. It's possible to luck out on the ballot step without accepting the "campaign + 40% affordable" option, but doesn't matter because if you stay solvent long enough for Schlage, Parkmerced, Treasure Island to complete phase 1, you will have no financial issues for the rest of the game.
You do want to go without union labor for Mission Rock because while it will pencil pre-crash for phase 1, you will be holding onto it until the late 2020s to build phase 2, and you want it to become pencillable ASAP so that it can complete phase 2 before the clock runs out in 2031.
There is a megaproject which appears pre-crash, just above 2670 Geary Blvd. You can get that building if you're lucky, too.
From what I can see, the optimal early game is:
1. Propose on Hunters, no labor, then sell for $6.4M.
2. Propose on Schlage, Parkmerced, Treasure Island, all no union - expedite permit on Schlage for a shot at pencilling phase 2 build before the 2020 crash blocks this.
3. Hire 3 more teams, take a: 2670 Geary Blvd - no rezone, 0%/fee, with unions; b: Mission Rock - no unions and ballot option C (full campaign/40% affordable); c: 450 O'Farrell St - 100% affordable.
4. When Schlage, Parkmerced, Treasure Island start to build, take the Presidio megaproject, 8 Washington St (100% affordable), and then move on to the most cost-efficient lots for 100% affordable development in Mission.
You will loss-lead while passing the first two investor reviews and nearly go broke, the 100% affordables will tide you over slightly, then your megaprojects will start completing and you'll be up ~$130M. You can drop Parkmerced, Schlage, Treasure Island at this point because they won't pick up value again later on.
At that point you are optimising for homes built. Max out the affordable fund on the most efficient/unpencillable locations. Start proposals on the high-density locations that will become pencillable as prices increase post-2025, get the prep work out of the way so they start constructing ASAP. If you got Mission Rock building without union labor you have a shot at completing phase 2 now.
There's likely more optimisation to squeeze here, but it seems too luck-based (like changing the ballet on Mission Rock, or going riskier on the early-game builds), I didn't explore it. The main risk is settling lawsuits early-game - this will bankrupt you before you can get a return from the megaprojects.