I'm afraid i quit lotro before plugins. Made it back a few times to see some new story chapters, but never bothered learning plugins. Laggy-combat-mounts and trait revamp were enough of an annoyance already. :P
GW2: Fishbane / Keyboard Not Found / Olaf Oakmane Planetside2: FishMcCool
The most usefull one is the one that sends freep coordinates. For a scout very handy. Safes typing. For Star Citizen I installed Voice Attack, many commands to operate my ship are done by voice. Maybe I make a file for monster play too.