[cypher]

How about putting some bigger shelves in then Chiela, you could make more use of the space that way, if you have a look at April's review here you can see how she did it, you could use more than one depending on how big they are at different levels & maybe use some smaller ledges in other areas.
I've never tried putting plexiglass over bars but it should work, I have just used cardboard & cable ties to cover smaller areas where I really don't want them to climb.