Naruto is the biggest spammer, but Obito is a close second i agree on that(spamm Kamui as if it was nothing, control Tailed Beast and Gedo Mazo, etc), then Madara also, and probably Nagato
There is nothing wrong with spamming, if it works for you why change it, the example of Minato for example, FTG and Rasengan are the key factors in his arsenal because there aren't many who could counter it, if it works why would you change it?