The PVP server has become dry over time and a revamp would be good
ELO reset/rewards - grinding ELO nowadays is boring and not impressive, when elo first reset being above 2k elo was impressive and was for the best but now anyone can get it because once you're 2k its difficult to get higher and people dont wanna play it therefore the competitiveness died. I'd say GAPPLE and BOW are the most played game modes so maybe they could reset once a month or so and the top 3 in each game mode could get rewards (euros, titles etc), this would no doubt revive the pvp server and bring back the competitiveness.
New game modes - EC already has plenty of game modes so removing a few dead game modes like horse, debuff (not nodebuff), vanilla and replacing them with more popular game modes like sumo, buildUHC, spleef etc would more bring more players and make it more fun
New Maps - PVPing is extremely awkward and irritating on unflat ground and, so making the maps completely flat with similar designs the the pokeball map and maps from other pvp based servers would make it more enjoyable.
Parties / Bigger team fight modes - As you probably know throughout the servers a lot of pvp teams / groups have formed over time and some times they would rather not fight on the game mode they play etc, so having a party feature on /go pvp would be nice so you could party split, red rover, FFA and choose teams yourself to organise team fights. This would again make go pvp more competitive
Command revamp - Some commands on the pvp server are confusing and hard for new players to understand for example /create gapple1v1unranked then /invite (name) is a bit much for just a quick fight, /duel (name) should be implemented and have unranked and ranked in a gui or /unrankedduel (name) /rankedduel (name), obviously they arnt hard to understand once you get use to but thinking about the newer players the current commands are quite difficult. Even removing this and putting the old commands here https://gyazo.com/15e95df07798d5b65938176248cc5150
KitEdit - An option to rearrange your hotbar/loadout once and not ever having to do it again would make life alot easier.(for example being able to choose what food in nodebuff, having your builduhc loadout in a certain order, gear in gapple in a certain order etc)