I'm old and jaded, but salary should be your primary metric. Stock options are worthless. I took a 50% cut at PagerDuty (YC10) for 2% of the stock options, they're now worth $1bn+ and screwed me pretty hard, the day after my father died. They didn't even offer any severance pay until I pointed out how much damage I could do to their reputation, then they gave me a week. Start-ups, especially run by new founders, don't know how to treat people humanely. Thanks guys. Since then my attitude is, "Fuck you, pay me". You will not win the start-up lottery. If they don't offer an 83(b) election, you could end up in the red if they do exist. This happened frequently in 2001, it even lead to several infamous suicides.[1]
Are you 200% sure you will last the 3/6 month signing-bonus waiting period? If not you could end up with a liability greater than the value of the bonus. I had this when when a start-up outsourced ops to LoudCloud. They contested our unemployment claim and I spent $3k in legal fees fighting them, in the middle of the start-up recession.
Start-ups will not invest in you as an employee, and will drop you without a second thought. Expect to spend all of your free time learning new skills just so you don't get fired.
[1] https://www.siliconinvestor.com/readmsg.aspx?msgid=17123680
(edited for spacing, and to add the anecdote about severance pay)