I'm doing Expert now, made a lot of progress since I posted. Eye/Worm/Skeletron down, going to farm up the mats to summon the bee, and I've already got a pretty long bridge for Wall of Flesh.
Using campfire cheese wasn't necessary in standard, but it pretty much definitely is for Expert if you aren't using hardmode gear vs. normal expert bosses. You really need to fight the worm underground, in a hallway, or you will get swarmed with the spit bullshit. Loading up on regen/ironskin pots, campfires spaced so you are always under the effect, and eating a marshmallow/bowl of soup helps a lot. I had to use the minishark for Skeletron, but primarily it was meleeing the shit out of his hands using the firey greatsword and then shooting at his hands/head when spinning. I highly recommend fighting Skeletron with the occasional row of blocks overhead, or you will be eating the skulls it starts spitting out constantly once you kill a hand for the entire fight, and they hurt. I had 31 defense(before pots) and the worm scarf when I fought him. 17% less damage taken is basically almost required since shit hits really hard and armor doesn't do nearly the reduction it did in standard.
It's doable, but you really need to farm the shit out of stuff. And getting lucky and having the goblin tinker guy spawn in the hive (apparently something he can do now) really helps, as I had all the mats for a few combined items, including the double jump flight boots.