Stop with the folded up posters imo. They are a waste. People don't pay for folded up posters. Get into the limited/numbered print business if that's your angle.
The quality of these CEs really needs to improve. Soundtracks are great, but most of the other stuff doesn't really have any quantitative value perception by consumers. Things people actually use are always cool. Playing card decks, mouse pads, cases, lanyards, desk figures, those kinds of things are nice. I'd really like to see some steelbook + soundtrack CEs. That's all it would take. Full color instruction booklets are really nice too. 30pg art books are dumb. If it's going to be an art book, it should be thick and meaningful.
I can tell that you guys are looking for ways to improve your CEs.
Most of the stuff you mentioned I place no value on. Playing cards, mouse pads, lanyards, figures.... don't care. The only CE items that interest me are art books (although, the ones that are included in the Signature Editions CEs don't do anything for me) , soundtracks., maybe a bonus making of disc... I don't mind alternative art work if I like it better than the standard release.
Putting in statues/figures will invalidate everything else typically. Mainly because they drive up the price for something that is almost always of low quality (probably why they are so often included).