Tobe! Isami

Both are highly comedic anime with a friendly cast of characters, likeable bad guys and somewhat amateurish heroes. 

Easy to digest shows with clumsy gradeschoolers being handed powerful weapons (giant robot / ancient energy weapons respectively) to fight equally clumsy adversaries in mostly "monster of the week" fashion. Simple but memorable character designs you won't see in any other anime. Very rewatchable. Despite the over the top settings, both shows manage to have very well made final arcs that still stay true to the show's formula. 

Both are humorus love triangles with one girl as the lead character and two boys, one hot blooded and one cool and calculated (voiced by Hidaka Noriko in both shows too) as friendly rivals and partners in combat. Hilarious liberties were taken with the respective source materials (fairy tales/the historical Shinsengumi).