Barring any official version of that (I’m not holding my breath waiting, lol), I use an assortment of modded crew bays to get the job done with as little waste as possible. With a couple that are somewhat smaller than normal and a pair that are huger than huge, I have more options to tailoring crew fulfillment while also adding as little energy usage and parasitic weight as possible to the ship. I know that’s still not as fundamental a shift as you’re proposing, but I happen to find this method to be fun.
One hull bonus that I’m really surprised nobody else mentioned yet would be…WEIGHTBOOST. This can be used to indirectly simulate different tech levels in service within a nation’s navy. The old stuff is kludgy crap loaded with analog gauges that would make a steampunk fan cry with joy, vacuum tubes, Leyden jars and the occasional dramatically-sparking jacob’s ladder (right out of a black-and-white horror movie). The new stuff fits on a teensy silicon sliver the size of a toenail clipping. I’m being cute, of course, but you see what I mean.