Thanks for the thoughtful response. It's nice to hear how someone else arranges things, and it gives me some things to think about.
We are both busy and work comes home with us (I work from home as a contractor and also have my own business; she often works late plus has a volunteer commitment that takes up a significant amount of time, mostly at night). I think this contributes to the fact that I feel like we don't get enough time together, even though we are home together much of the time, eat dinner together most nights, see friends together on weekends, etc.
I think a regular date night would be good, and it's been a while since we've done that. Especially if I am seeing someone else, I think she will need that. And I need the quality time, not just quantity. I think that regular time focused on us as a couple would strengthen a lot of areas that I am feeling are weak right now. So thank you for mentioning it. Seems simple, but it's something we've lost track of.
I'd love to be at a place where I could see someone 1-2 times a week, but I don't even manage that with good friends. It's a moot point anyway, since the person I am interested in is only available once every 3-4 weeks, which right now feels fine and comfortable for everyone, and plenty slow enough for discussions between times.
At any rate, we are not talking about extensive amounts of time away from home. It also looks like it would overlap with times when she is busy. Or like a couple weeks ago, where we all socialized for part of the evening and then she excused herself to finish up some work. I do think there is the potential for a level of friendship between them, which is one of the only reasons I am considering it at all right now. Frankly, if we can't all be at my home and socialize once in a while, it's just never going to work, anyway.