Well, if ya check out Rick Reid, you won't hear much swamp pop! Rick Reid spends most of his time listening to a lot of Travis Matte, drinking Budweisers and tellin' lies to pretty girls.
But I do agree with you about Mel Pellerin. His tune about Holly Beach is one of my favorites of his (My Little Cabbage runs a tight second). I'm not an expert on swamp pop, but I'd say Cookie & The Cupcakes were probably the pioneers of the genre. And to reiterate, Johnnie Allan is a guy I can listen to anyday -- anytime. I just like his style, his voice, his jewelry and he's got an awesome barber.
I think the swamp pop signature is the horn section, for sure. The tenor and alto saxes with a trumpet accompanied with a piano. To me, that's what I hear when I think of swamp pop -- kind of a blue-eyed soul with a li'l country twang.
A lot of old-school zydeco artists mixed in a respectable amount of swamp pop into their repertoire, albeit with a piano accordion on top a bed of horns.
So really, it kinda depends on the style of swamp pop that makes you grin -- there's a Cajun/country style and a Creole/R&B style. I'll tell you this -- it's all good...