I very rarely watch channel trailers, however, I will say, I find they work great with Gaming channels, especially those that cover a wide variety of games. But instead of standing there telling me "i like this or that" why not make a compilation of sorts as a best of, to give us a very quick look at your sense of humour, your quality of commentary etc.
channel trailers like this have made me consider subscribing to channels that on first view seem like 'here's 5 million videos, good luck' and im too far out of the loop to get into their content at this point, but instead show me some short clips that are almost viral worthy to get me interested to be there for future fun moments like that.
overall, keep a trailer short and sweet and consider how someone who stumbles on you would be looking for (its usually to be entertained) I say go for it!