Elemental Bombers are really something. You have access to some pretty sweet AoEs and are able to deal real damage even without good gear, which makes soloing and party play cakewalks. You're able to switch through four elements and you have access to a shield that works differently with each of them which makes you pretty versatile too. Downsides are the X-spamming and squishiness.
Glacial Masters are different. They don't have range and AoEs like Elemental Bombers since they're much more in-your-face and combo-y, but GMs still pretty damn strong and fun. Thing is they're more of a PvP class and you definitely need funding for Glacial Masters to do passable damage in PvE. They're squishy too, which means you have to be extra careful.