Indeed the servicy slice-of-life part is what I love in this anime; it could look and move better, but having images is better than the occasional drawing and a long-ass description in a language I don't quite understand.
But like most semi-serious novel adaptions, the serious plot is utterly destroyed. I am not really certain that skipping it almost completely (as they did in the second season) is the best choice. Until now the only anime that managed to combine ecchi with plot is the monogatari series.
PS: and finally, I'm free again so back to Seitokai DxD and Yukari's debut