Originals, of course, but they have to be GOOD.
And therein lies the problem.
"Here's one we wrote," says the cover band dude, and then everyone hits the bathroom.
We've all seen it.
"Play some Zeppelin!" shouts a drunk.
I went out hard pushing my originals, years ago, and found the music business to be tough. Now I just get by, playing covers, and maybe if I can find some originals that fit the genre we're playing, I'll throw them in, but that hasn't happened yet.
We have a favorite local band around here, (they're not MY favorite,) that everyone likes to tell me "should be national." They are a pure cover band, and I always answer that by saying, "with WHAT SONGS????"
Your band is only as good as its songs. My band is the best classic rock band there could ever be, because, as a cover band, we play the best classic rock songs there ever were.
Doesn't mean we'll get any kind of real reward for it, though. The songs were somebody else's hard work; somebody else's creativity.
I don't really get "covers vs originals" as a discussion.
I do think every player should take a good turn at both.