Okay, so I'm not as confidant about this anymore after listing out the weaknesses, resistances, and risky STAB options. It sounded like it fit well at first because of being the only possible typing besides Psychic/Bug to be weak to all of Pursuit, Stealth Rock, and U-Turn, but especially listing out the weaknesses and resistances makes me think this would never get the chance to switch in, at least not without some kind of immunity-granting ability like Flash Fire. Psychic/Ice might still be worth considering, though, if we feel like being especially... let's say "brave".
i think this is true for the psychic typing in general and that's why i don't really like it for this cap. psychic has exactly one thing going for it: it performs well (at the very least, solidly) against most fighting types, in a vacuum. it's a terrible typing otherwise. it has very little reward to offer in exchange for the risk. the only way i can see it working is if we do what game freak has done with the psychics that already exist: give it a huge movepool and very solid ability. i find it hard to mesh that with the concept of this CAP.
i feel some slight agreement with grs cousin in that dragon is not an especially risky typing in and of itself. we'd have to make sure that it'd only be able to abuse its dragon typing with the riskiest of moves (draco meteor/outrage... and as von notes, there's not too much risk involved there anyway) in order to prevent dragon from being the falcon punch of its typing.
as for bug though, i don't feel much risk in its movepool so there i agree, but in terms of typing, it does a very good job of balancing risk and reward. i also think it's easier to fiddle with movepool than it is with typing, seeing as movepool is so granular. i am aware that this is really an overly generalizing example, but just throwing sucker punch onto its movepool as an afterthought would already crank up the risk - many many mons run unstabbed sucker punch so it's not like that choice would be ignored.
finally i will agree that bug is not the only option, i'm liking ice and starting to warm up to grass. just that it's the one i like the most. it's just, like, my opinion, man
and eagle, no hard feelings =P