Those are some big ships... I've often debated having a population ship, with 5 cryo tanks to every 1 habitat module, though this would get big pretty quickly it would allow you to very effectively move a population into a new colony instantly. Add some cargo for carrying mines/ordinance production/etc and a tractor for carrying a shipyard, and you've got some economic push that will move on command!
I've debated using this idea to create a nomad empire, that sets temporary (10-15 year) colonies on rich worlds before moving on. Namely just stopping long enough to perform some research, refitting, resource collection, and repairs. This would, of course, require some massive civilian ships... But putting an orbital habitat on a ship should make it produced via industry, right? That can cut down a bit on the massive shipyard costs and provide some living space.