I'm a bit addicted to it too (all I did was add another cage on), but I have to keep saying to myself if I make Sen's cage any bigger it'll be TOO much cleaning! Haha. And we don't have space to store things. :P
If you have space to store I don't see why not?
I'm just gonna focus on making a tube-city for Sen. I have more straight tubes coming tomorrow, so I'll take apart
the loop I've put in and probably add in another hole for tubes to go in, on to her extension cage... although, I'm not sure where, as it's pretty full... lol.