I cannot stand Bastok, for reasons stated above. It's just so fugly.

Windurst is definitely the best looking of the cities, not to mention the largest of the three. Some people complain it's hard to get around, but once you know where everything is, it's not so bad, especially with the tarus that will warp you across town.

I've also started in San d'Oria. It's a good city, though it can get slightly annoying. The San d'Orian NPCs have an Elvaan superiority complex that can get quite irksome. On top of that, while the BGM is nice at first, it gets really annoying quickly, though I suppose all the BGM does, which is why I turn the in-game music off and pop in a CD.

I'd go with San d'Oria if you're going to go for PLD. The monsters in Ronfaure are more suited to melees anyways, and the San d'Orian ring is nice too.