sam's still right. all kinds of red flags -- "i'll give up my job, but only if things are going well", "i have 2hr/day to spend", resentment already building, etc. it's only gonna get worse.

number2 -- that's fine that you have those priorities (family, steady job), but it seems like you're in denial about the situation. absentee (or remote + part-time, whatever) cofounders are not what early stage startups need. and even if you disagree, your potential investors (e.g. yc) won't. if being remote and working 2hrs a day was a viable strategy for a startup founder, don't you think there would be more success stories that fit that profile? :P

that said, you can still come on board later after #1 gets things going.