Fights aren't supposed to be pretty. And by saying that I mean there's a difference between matching yourself up against someone under a set of rules in a sport match and actually dumping all your anger on someone or fighting for your own life. In the first case, you have a display of technique, physical capacity, perseverance and strategy - high "pretty" factor. In the second case, you'll have two people trying to either hurt each other the most or get away alive - definitively pretty ugly.
Fights are mostly quick and simple (weak x weak, strong x weak) or too darn long and boring (coward x coward). Even when two strong guys fight, they're usually so angry (or just plain dumb) that all they'll produce will be a brutal bloodfest, like the UFC matches nbotary mentioned. No blocks or dodges, just trying to impose the most pain in the shortest time.
That said, it's not impossible... but only in very special and rare moments will you see a pretty *fight*. Once-in-a-lifetime fights. It's what happens when two skilled and resistant men meet each other in one-on-one, no rules battles. Like the one between Bruce Lee and Wong Jack Man, in San Francisco. The moment when two men perfectly aware of each other's strenght, and of how easily they can kill or be killed by another man fight it out. They couldn't just go all-out like bulls, because every punch, grip and kick has the potential to kill or cripple; nor would "dirty" strategies result in a shorter fight, since those are also expected in a life or death situation. That's the only chance to see everything in the book, defense and offense-wise, put to use.
You can then understand why they're once-in-a-lifetime. There aren't so many of those men, and it takes a miracle for both, if any of them to be able to fight again (reason why sanshou championships had rule changes). Also, they don't get into life-threatning fights that easily. Well, Bruce Lee picked every fight he could, but there hardly was anyone that could last too long against him.
Anyway, if I had to pick one, I'd have to say fights are ugly. But that's the same as saying that boxing matches are all commercial - every now and then you see something to keep your hopes alive.
P.S.: Adress to the famous article about the Bruce Lee/Wong Jack Man fight.
http://www.kungfu.net/brucelee.html