LifeHacker has outlined what they see as the top 10 Mac utilities which I think are well worth a consideration. I actually use some of these myself. However, I’m definitely not that enthusiastic about Onyx (Cocktail is safer) anymore and I’m not sure that the role Growl should play now that we have notification center.
The others seem fine to me except that you might think about purchasing products in place of these such as iBackup, AppDelete, MenuMeters (iStat Menus Pro) and QuickSilver (Launchbar and Alfred are my two favourites). I do think it’s always useful to see this kind of information. This is actually one of the much better sort of must have top ten apps article I’ve seen.