I'll toss out some of my own addons here, just because I find them entirely too useful
Click Menu (cause convienance yo)
BobHUD (lightweight hud I use for pvp)
RaidFrameResizer (cause those blizz raid frames don't make themselves small enough)
LightweightViewPorter (my own ridiculously lightweight viewport addon I don't use myself, lmao)
SpotMe (someone requested it, ok?)
for other addons I used
Numeration
rFilter3