firstly, don't let anyone tell you what "good" or "bad" roleplay is - it's entirely subjective! nobody is a roleplay "expert", and certainly not on gtaw. there's really nothing wrong with a short or long /me provided they don't provide anything to the audience that isn't an action (a thought, for example)
i think it's a bit of an erroneous expectation for people to want more than /me chuckles - there's really little more you can describe there without breaking out the thesaurus and webmd
lastly, since you're looking for specific advice, i'd keep length of your /me's relative to the situation - if you're in a packed crowd, keep them short to be considerate to other players. if you're with little people, i'd say let your juices flow. again, all of it is subjective