Examples of strong males leads that the players have largely liked (even admittedly by Jagex). These are off the top of my head:
Nomad (killed off)
Zaros (written out because too powerful)
Zamorak (written out because bad guys can't win)
Saradomin (written out because too powerful)
Armadyl (written out because too powerful)
Bandos (killed off because of a player vote)
Lucien (killed off)
Sliske (killed off, then attempted revival but writers then killed him off again)
Icthlarin (written out, possibly involved in Necromancy, too powerful otherwise)
Azzanadra (written out because too powerful)
And characters involved in the current Runescape storyline:
The Raptor (written out in a story he wasn't the focus of. Was an afterthought to give a more important character characterization.)
Death (main character in Necromancy)
Zemouregal (not written off yet, active in the current story with morally ambiguous intentions).
I don't want to blame a specific JMod for writting these characters off because I don't know for a fact but it seems like all of these characters were written off because as Jack said, the writers do not like writing about them.
Edit: I forgot Kerapac. Especially Kerapac. Kerapac is probably a better example than anyone on this list but his death is well justified as he sacrifices himself to kill one of the longest running antagonists in the game's history.
Vindicta is a strong female character that's preceived positively by the players as well.
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