I suggest you revamp spawn pvp. people are able to jump to spawn while pvping. And add a plugin that disables enderpearls when you're combat...
*add hostile mob spawners *add the ability to buy w/o tp'ing to shop *decorate shop it's mediocre. *add enchantment books *add better ways to earn...
add a public xp farm fix pvp @ spawn (add combat log) hold dps every month