I've carried a bit of hotmelt caulk-glue stick in my repair kit for many years and have found it useful - probably are some older posts someplace where I've mentioned this previously. Everyone in my family has a repair kit in their ready packs and a bit of hotmelt is in each kit. An entire stick is too much IMHO - 1/2 or less of a regular diameter stick should last a long time in a repair kit.
As for epoxy - big mess. However, a bit of 2 part epoxy putty carries nicely - low tech is cut a bit off and wrap it in cling wrap before stowing in repair kit. More durable is to vacuum-seal a bit before placing in kit instead. The putty should be checked or replaced about annually, although I've used bits that were older.
Interesting idea with the clothes pins - I don't think I've ever lugged any around except in "the big green box" (chuck box for car camping) so can't comment on the value. Minime's small binder clips can be quite handy as well, and I have used them from time to time, but they also are not something I've deliberately carried afield.
I don't think I'll add the clothespins to my kit, but I wouldn't make fun of you if you did - you obviously can see what things MAY be used for instead of simply what their intended use is. You pointed out a use I hadn't considered, so thanks.
Regards,
Tom