I think most of what you suggested is either already a possibility in the game's current or upcoming version, or it doesn't make a whole lot of sense. To me at least. What does it mean for crew number to be "based on infrastructure rather than crew quarters?" Maintenance is already free for orbital habitats, so long as they aren't classed as military. Don't want engines on your space stations? Don't put them on, then. And I'm not really sure why being a space station would make shields in particular work differently.
Distilling down the new feature requests to their essence, it seems like you want a tow-able colony nucleus, usable as a regular colony regardless of position. That's an interesting request, and mirrors a long held desire among some forumites for tow-able asteroids.
I don't think it will happen, even if it might be a neat idea. If Steve was jazzed about the idea, he probably would have made it happen years ago when the tow-able asteroid idea was first suggested. Moreover, the current and near future ability to create remote, non-planetary bases at arbitrary points is being built around the idea of those bases being logistically supported by more traditional planetary colonies and industry. Hauling maintenance supplies and fuel and ordnance from one colony to a station in deep space is logistically interesting, requiring the player to manage the flow of resources.
