The issue with T'challa are in regard to signature stuff are many:
- a lot of his intelligence and tech feats are done "on the fly." Such as Thanos busting machine, a mutant gene suppressor, ect.
- a lot of his intelligence feats are prep feats
- "Wakanda" gets credit for a lot of stuff as BoG mentioned.
- retcons took away his largest tech feat as The Cool Thatguy said. Dude basically built Wakanda tech from scratch
- nothing transfers run to run to become "iconic" or "known." Hey, remmeber the technojungle? that tchalla built for funsies?
- when people like Reed, Stark, and Pym were building stuff during the early days (which is when things become iconic in the comic realm)... t'challa was busy either not having a book or being a background Avenger
- T'challa's world doesn't revolve simply around tech. All Reed does is build deus ex machina stuff. All Stark does is build armor and weapons. All pym is known for are pym particles, ultron, and slapping janet. T'challa is known for Wakanda, Vibranium, King, warrior... AND then tech/brains. You can make a whole book where T'challa doesn't build a damn thing and it works. You can't really do that for stark or reed.
But anyway, I would go with:
- He gets credit for designing his vibranium weave, which is his "signature" thing, as mentioned in Rise:
https://1.bp.blogspot.com/-cbtqyp_2k...2Brise%2B3.JPG
- thrice blessed armor
https://4.bp.blogspot.com/-FRLgfyE5y...udlin%2B19.JPG
- shadow phyics and knowhere room
- life raft
https://2.bp.blogspot.com/-SJi2HLpvj...%2Bav%2B42.JPG
- techno jungle
https://2.bp.blogspot.com/-FdEBdlAYN...%2Bf4%2B53.JPG
- basically all of wakanda's advanced tech shown in the classic age pre-priest
- then he generally gets credit for the quinjet when writers remember and falcons wings but once again... that could be more "wakanda"