then you need to confront your situation and resolve it satisfactorily, because staying in late to get your "real" work done is means to an end, remember you have a "life"!
However, my experience is that pair programming would work well in a senior/not as senior pairing, with the caveat, you need to have capacity on your projects to roll with this also technique.
regarding you choosing to sweat on your startup, fair play thats your choice, and possibly a good one if that's what you are passionate about. hopefully your end goal/mission is not just to make loads of money though!