There's really only two choices if you want a combo plinker and hunter; .357 or .44 mag. The .357 will be cheaper to shoot, but the .44M will have more punch. The .45 l. Colt is a good round but not commonly enough available to qualify as a plinker. The newer .454 and .480 are not common or plinker candidates at all.
I like the old pre-safety Marlins.