I feel like The Office was hyperextended way beyond what should have been its life expectancy.
Arrested Development was still fantastic when its plug was pulled. It was nice to get the opportunity to revisit it. I really enjoyed season four, but I agree that it was missing that group dynamic from the first three seasons. Prior to season four I was always aching for more Arrested Development, now I feel content with it. If there is more, that would be fun, and it would be nice to see a conclusion to the dangling story threads of season four, but if this is the end, I'm okay with that.
Though within the storyline, all the characters are in the same area at the end of this season, if they can get scheduling worked out, it would be nice to see them all together again.