Anime wise I tend to go towards Science fiction/fantasy/horror types of shows. I do enjoy shonen but I don't thing I could read something long like naruto or one piece or a slice of life high school romance. Don't really mind if it's a complete or on going story.
Just a few suggestions off the top of my head for series that are not too long and have either finished or are ongoing (but not into hundreds of volumes):
The Ancient Magus' Bride (dark fantasy) 6 volumes ongoing
Tokyo Ghoul (horror) 14 volumes - complete, although I think not all published in English yet?
One Punch Man (science fiction/shonen) 11 volumes in English so far (ongoing)
I'd also recommend a classic shonen series like Dragon Ball Z (which can be bought in omnibus editions) because Toriyama is well worth reading, even if you've already watched the anime (for all the little details and the humour)
Parasyte (classic horror/sci-fi series) 8 volumes
No worries dude, I've only read one and that was years ago; can't even remember what it was (it was loaned to me from a college friend and I don't think I even finished it). I love the art of manga though