Haai gaiis first post here so go easy on me mmkayy.
I believe that getting everything at once or figuratively speaking "eating all your hallowen candy at once" just takes the maximum amount of joy and effort away instead it should be one step at a time same goes for a player becoming a emperor over other people. I'm thinking of a system similar to what Warhammer online had when the opposite faction raided lets say the inevitable city it was all in stages you couldn't progress from one level to another before unlocking it. It some of these obstacles have tripple locks, and all this time enemy players will hold the line to their city from stage A to B. B stands for boss.
Right now I'm not really feeling it for me atm it looks like take the keeps, some supply farms, and completely obliterate the other two factions = emperor. Correct me if I'm wrong.
Have some involvement with the Imperial Throne like having PvE in PvP and PvP in PvE each simultaneously co-existing with each other in a symbiotic relationship
of synergy. And when a faction takes control over the imperial throne let the imperials become the factions imperial guards, so its not that easy to Coup d'état the emperor along with the emperors faction as his vanguards as well.
Creating a never ending end game content just solely by the personal quest of a player to go for emperor.
Just my two cents here.