Seen my share of those of both: as an airman in the USAF (We called them just plain 'gung-ho', which, by the way was a term first derived in Korea/Vietnam War); and as a Medic in civilian life, (we called one of those a 'Rescue Randy')
It is kind of crazy, but I don't see Riker as a 'gungy' type of guy. Dedicated? Sure. But not gung-ho, at least to me. If anything, Picard is more gungy than Riker, especially in the early seasons. Once again, at least to me.
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I never snitched on anybody, and I never kissed anyone's ass. To me, that's the worst thing you can be in the military; A hall-monitor, brown-nosing little snitch boy. Either that, or a REMF (you can ask your husband about one of those)
Wow, once again off topic. In terms of a gung-ho guy, I don't think Riker quite fits the bill. There are plenty of examples where he is the reciprocal opposite of gungy in the series. To me, a truly 'gungy' guy is a negative term for personnel giving stupid, dangerous orders without common sense or accountability, getting soldiers killed in the process.