♦ Is EU good? » Depends, it's the more difficult version in comparison to JP for example. If you like a challenge then you will like it. (We also get more SoulCash for our money)
♦ Are there raids? » Yes, there are currently 5 raids (a 6th one coming up soon). 4 of these raids are found in each of the 4 cities, the 5th one is the Golden Citadel, which you have to enter with a team of 4. (It's the currently most difficult raid, but also drop's the best gear, etc)
♦ Are there guilds? » Yes, of course there are. They don't have extremely big impact being in one, but they are nice little communities and a good way to get to know other players!
♦ PVP? » Yup, you can fight vs other players in District 6, which is where people usually 1v1 (District 6 is the Zone you have to travel through to go to other cities and it's open-PVP there) You can also fight in Dimension Trip, which you can only queue up solo (Not as a Team of 2, what someone mentioned). Usually you will probably get your butt kicked, if you just reached lv55 or something like that, but with better gear and the more often you try it, the more success you will have. Higher places in the PVP Rankings also yields more rewards!
♦ How balanced is it? » In which terms are you talking? The grind is fine until around level 50, then it's little pain to level to 55, but once you reached it it's fine. Classes are decently balanced, each having their own pros and cons to them.
♦ Is community active? » Yes the community is very active on EU & NA (as far as I know)