Season 6 is my favorite season, so I have no room to argue the merits of a good season, lol, but S7 is still high on my list, although, I do agree with Revolver and the too much Potential screentime problem.
I think the reason no one ever took to the Potentials was because, for the most part, they were set up to be throw away characters, to be killed off if and when it was called for by the script, so not a lot of effort was put into developing their individual characters, with the exceptions of Kennedy, Rona and Amanda. But because of this and the fact that they were given so much screentime, no one felt emotionally attatched to them. We didn't know where they'd come from, what they had to go through to get there, how long they'd known they were Potentials, or how they felt about being potentially the next Slayer in line. So we were left thinking 'why should we care about these girls? They're sucking away all the Xander/Spike/Anya/Dawn/insert-character-name-here time.'