This is something I would like too, but I would go even further than wallpaper and flooring. There should be a bunch of different room designs we could buy (design as in the shape/size), and we should be able to move stuff around and put it where we want it (even the market/fitting/star map/etc stuff). I also want additional/different furnishings, maybe a window and be able to change the scenery of what's outside to see different planet types or stars or asteroid fields etc (or have a multi-cycle thing that randomly chooses one of however many installed sceneries each time the MQ is loaded). Hell, charge aurum for it, it'd make CCP money, I know I'd buy some of that stuff. It is pretty low priority, but playing dress-up is always fun.

Customizing would be difficult from a lore perspective. Since there are almost as many stations in New Eden as there are planets, it would be difficult to keep track of all the customization..

From what I can tell, the personal spaces we have now are going to have upgrades as according to the "Need more space?" advertisement in the War Room. They may eventually add customization (similar to PS Home spaces) bit I think they are still figuring out the space upgrades for now.

Yes. There's alot said over the intercom if you pay attention. Some things said appear to be for humor but others are hints for what's to come.