But I'd like people to at least have animal suffering on the radar of "things I'd like to give a shit about, if I had the energy, and that if it became much more convenient to care about, I'd make small modifications to my lifestyle." So that when in-vitro meat becomes cheap and tasty, I think people should make the initial effort to switch over. (Possibly even while it's still a bit more expensive).

This is pretty much the case for me. I was vegetarian for a while in high school–oddly enough, less for reducing-suffering ethical reasons than for "it costs fewer resources to produce enough plants to feed the world population than to produce enough meat, as animals have to be fed plants and are a low-efficiency conversion of plant calories, so in order to better use the planet's resources, everyone should eat more plants and less meat." I consistently ended up with low iron and B12. It's possible to get enough iron, B12, and protein as a vegetarian, but you do have to plan your meals a bit more carefully (i.e. always have beans with rice so you get complete protein) and possibly eat foods that you don't like as much. Right now I cook about one dish with meat in it per week, and I haven't had any iron or B12 deficiency problems since graduating high school 4 years ago.

In general, I optimize food for low cost as well as health value and ethics, but if in-vitro meat became available, I think this is valuable enough in the long run that I would be willing to "subsidize" its production and commercialization by paying higher prices.