The following is for 121 day trips only...
I'm doing a lot of day trips recently. It's nice to be in my own bed every night. For the GDL turns, by the time I get home (830pm) the son is already asleep and the daughter is in bed, so far I catch her awake and read a quick story and good night/tuck in. In the morning, I can see both kids before they head to school but I don't have time to drop them off. For other day trips that check in later, I could drop them at school. There's one day trip that is early (6am) that gets done about 130pm which would allow to pick kids up from school and spend the rest of the day with them.
I see the point about day trips and not quality time at home, but it all depends on how far from the airport you are (I'm pretty close) and what sort of hours the day trips are.
Biggest advantage to day trip lines is that they typically DO represent the highest day off lines. At our shop, if you have 19 or 20 day off lines, they are almost always exclusively day trip lines (highly productive day trips).
So you still get a lot of quality, true days off at home. And home every night to boot when you are at work.
Lets put it this way, when you do a multi-day trip, you are guaranteed 100% to be away from home. With day trips, I'm still home a portion. Either I can see them in the morning, the evening, or both. It all depends on the kind of day trip it is. With a 4-day trip, I see them on day 1 before leaving (if the hours are good) and day 4 after coming back (if the hours work out good). Day 2 and 3 are guaranteed to be away from home, and day 1 and 4 you may or may not see the kids.
The last time I did a 4-day trip was December! This lifestyle now is so much better. I do have a 4-day coming in June, not looking forward to it LOL.
" The alternative option is to fly light twins for a small, but growing 135 operator. Home every night, although work days are long(especially in the summer), and only one day off a week. Single pilot, New England weather, so lots of low altitude IMC. I almost feel like it’s a right of passage, and a really cool "
6 days on and 1 day off? And in single pilot hard IMC? No way. Go to 121 flying. You'll have FAR more time at home and much more comfortable flying. Your wife and kids deserve better than 1 day off and some single pilot 135 outfit - especially in this market. Go 121 and don't even look back.