You can't move onto Peridot Coast as that's currently unavailable on the free version of the game. You're pretty much at the end of the content.
I haven't played in a while, but try a spell build, max dex and get more dex capacity to reduce spell cooldown as much as possible (i had 65 dex)
I think spells also benefit from int, and my favorite spell is the one with rotating projectiles going outwards in a circle (best aoe dmg imo esp for ranged enemies)