Weird al is a rather obvious.
But Axis of awesome is also a sheer favourite of mine. their four chords song is a genius composition mashup of many iconic songs throughout the years.
Whitney Avalon is a very underrated one who does some really good and rather witty pop culture themed songs.
Least favourite: Dennis Leary (He lives up to his name)
Victor Borge has always been good for a laugh. Very Looney Tunes.
Piff the Magic Dragon.
Jonathan the Terrible
Tiny Girl Big Show.
Jacques Ze Whipper.
Gallagher isn’t my favorite but idk if I’ve seen enough to say he’s a dislike.