While I'm not specifically into chains that much, I think it could offer a nice alternative for the bondage there is already in game, and what you've made so far looks very, very nice. A few comments/preferences I would have:
- I think they could be slightly shorter/tighter, i.e. without that much of a visible slack (so that they look actually sort of restrictive). Now I know you mentioned that things get weird when they are too stretched, so it's probably a question whether it's possible to set it that way and still make it look good. Or possibly two versions could be made, one shorter and looking more restrictive, one looser?
- I'd say framerate is the priority. Or there's just as well the above route again, with two versions, one more detailed and less FPS-friendly, one simpler and more straightforward. My SDT slows down heavily with mods, unfortunately, especially detailed ones.
- RGB sliders are always cool, but if impossible, I think the good old black is the best choice for any bondage gear - makes sense for any kind of scenario. Or if chains, then of course a dark grey.
- I like the "jewelry" idea very much personally, I like elegant-looking bondage a lot, but then I can understand if that's not priority.
- I'm with you on the "a bit squeamish" idea, I like some bondage a lot, but would be grateful if none of the things you listed appeared here.
As for pictures, I have few at the moment for chains specifically, but I might dig something up (and may do some looking, you know, in the name of science). Unfortunately I can't promise miracles.
If there's any specific help you need, please let me know - I can't promise miracles here either, as my mod-designing skills are non-existent so far, but I'll see if there's anything I can do.