Like MM, I have a couple of favourite parties/races/classes, but there's a definite possibility to replay those you've never touched before, and once you're experienced enough to know the game, these can be fun.
A further comment though, the unavoidable combat isn't just annoying for the bosses. You have to be on your game, strategy-wise, or even "simple" battles can go badly if you get lazy. For example, attacks from the side and behind are more dangerous, and the monster AI is clever enough to surround you. This adds immensely to the realism and enjoyment of planning out individual combats - at least for me - but like anything else, after a while it just becomes another tedious part of setting up for every battle. Many times you'll cut a few corners trying to push quickly through yet another battle, not set up certain buffs, they'll get a lucky hit on your mage you didn't bother to protect in the back row, then your healer will go down, then your backup healer can't keep pace and it's reload time *sigh*
But it's a great game!