Time to upgrade...??

I have a planted 29 gallon with approx 45 fish in it, YES I KNOW...before you freak, keep in mind alot are small tetras, barbs, panda cory's etc. I have a large pleco and large Syd. cat. and i think its time to rehome the SYD as well as some rosy barbs and what not but even after doing so im going to have about 30 fish. Is this a huge issue as long as the tank does not appear to be overcrowded?? There is a TON of open water space but no reak open gravel as its all planted and covered in large rock and driftwood. I have an angelicus loach and a bumbleecat as well as a banjo cat that hide under the logs...... if the community seems ok is this an issue? I want to upgrade to a 55 but my landlord worries about the strength of the house as I am on the thrid floor.

ANy thoughts?

well, its hard to see EVERY fish, but there are atleast 12 guppies, tetras and mollies you can see... my tank has as followed....

2 Bandit Cory's
2 Panda Cory's (TINY)
2 Rubber Plecos (tiny)
2 Common Plecos (1 large 1 small)
2 Sydontis Cats
1 Bumblebee cat
1 Banjo Cat
1 Spotted Rapheal Cat
1 Angelicus Botia
1 Juli Cat
1 Clown Pleco
5 Cardinal tetras
5 Black Neon Tetras
3 Cherry Barbs
2 Mollies
2 Guppies
2 Bleeding Heart Tetras
2 Rosy Barbs
4 Zebra Danios
4 Swordtails
2 Green Tiger Barbs
1 Otto Cat

4 Assorted Snails, and whatever else is growing in there....

Ohh I forgot,

1 Zig Zag Eel...but he only comes out at night....

See, I cant put a bigger tank in here because of the weight.... I would transfer everyone into a 120 gallon and call it a Day!

even if i do that, as the pleco's grow larger they are going to need more open floor space correct?