Mr Cobra,
The file sizes for the meshes are fairly small. My largest clubhouse model is Riviera and it is 106kb. The problem is the textures which can be much larger in the 12-20MB range. They do compress quite well when packaged through Unity though.
However, the limitation of a community Dropbox, for me, is the ability to actually see what you are downloading. It would be nice to scroll through screenshots of available models and selectively download the ones you want. There are obviously 3D sites and texture sites but nothing that condenses it for our needs here. So, a dropbox like site where you could control the "home page" so to speak for the provided file would be perfect. Merge Imgur and Dropbox for me and we might have it. Maybe this exists?
Even just a locked comment thread might work where each post contains a single photo and a link to the file to be shared. However, as sharing gets larger, that thread becomes cumbersome to navigate.
Once this is up and running it might be an idea for folks to simply bookmark the site URL then on this forum you only need one posting containing that URL. After that everyone looks after themselves.