Hattori Mitsuru does some really wonky stuff, like the one with the sex hamsters (Otogi no Machi no Rena) and is usually fun. The art has this huge cheerful energy about it and so do many of the characters. But frankly, the longer series often have serious weaknesses. Either the plot spins out of control, or the mangaka gets lazy and there are dozens of chapters of lame filler (Umisho, I'm looking at you). With oneshots there's no time for any of that, so these little stories kind of have the strengths of Hattori Mitsuru without the weaknesses. They're pretty nice. No sex hamsters though.