Good point on vesting. Chances are that your vesting would start when they start giving you equity (if they eventually do). Even if they were to give you the same amount it's not fair to you to have to wait a couple extra years to finish vesting.

The risks you're taking right now will also look a lot less once the company gets to revenue neutral. "we made it, so it wasn't that risky after all…" it'll be easy for them to negotiate down at that point.