Sending out another shout-out to @phenylketonurics here, with his other comic, There's No Such Thing As Jason. I just love all of the characters in his comic, but Jason/View really stand out to me, from trying to figure out who the hell they are, who's real, and seeing the dynamic between Jason's fidgety, nervous, awkward nature to View's wild, impulsive and crazy attitude. I never get tired of seeing these guys.
Also, @Louistrations ' Apricot from Apricot Cookies. Really, the whole cast of characters are fun, but Apricot is just so damn cute and has so many great moments, it's hard not to recommend her.
@blackopsracing321 's Asher from ABDUCTED is also really fun to watch. He reminds me so much of Morty from Rick and Morty. I totally picture that voice actor doing his voice.
I could go on all day mentioning characters from the various comics I subscribe to on here, but I don't have all day, so hopefully some people can get some kicks out of these awesome protagonists.