I think you should look at the design of the wall 1st mate. Go raid your garage for piping, wiring, screws, old electrical devices u an butcher and what not, and see if you get inspired by it. Maybe add a doorway and put some red lighting in so it glows through maybe. Glue and mold everything in layers then spray it black, silver or brass then dry brush it to death. Then add the bio's, trophies and weps etc.
Thats the kinda thing im gonna do if i ever get round to making mine. Im sure if u can design and make it bulky enough for the bio's u could just prop em on there. Personally i think id use nails and a wooden board, then bend the ends sticking out so u have a L shape, and then put shaped milliput or plastic etc on the end of each 1 for the bio's to be stuck on using a bit of blu tac or double sided sticky tape. If u used nails that were really long you wouldn't have to worry if their to short. Plus u could bend them as much as u like to get the desired angle for your bio's, and just trim the ends. Or you could do the same thing but with 2 or 3 nails per bio and remodel them with milliput so they look good on their own without the need for anything extra on the ends of them. Magnets would be the best bet i suppose lol.
Its just an idea i haven't put much thought into it atm tbh.
