I've been playing since the beta on the PS3, but I've taken long breaks in-between subs, so I often end up getting to the end game content well after most players have already mastered it or at least well outgeared it to make it significantly easier. When I fought Titan HM last year he was still kinda hard, but now he's a total joke.
I did get to experience Demon Wall in all its BS glory though. I did not go in with full Darklight, which fortunately the people I grouped up with were not total dicks and didn't leave because of that, but we did wipe quite a few times against that stupid wall. Now its kinda second nature (not to mention overall just an easier fight), but making sure everyone dodged those telegraphs perfectly to not get knocked off and instant killed while simultaneously trying to DPS down those stupid bees as quickly as possible was quite a task. I can only imagine how much worse Titan HM must have been that first month. I do not regret waiting on that one.
There are some things I kinda wish I had been able to experience when it was still fresh and actually worthwhile. I never bothered with the Binding Coil because getting a raid group together is kind of a pain in the ass and usually requires the kind of commitment and expectations that I don't really like to get involved with in an MMO, but I do kind of feel like a missed out on a big part of the game.
I had no idea gil was ever an issue on Leviathan though. (At least not any more than any other server.) I've been there since day 1 and I always felt like I had adequate gil on hand, but I suppose I am pretty frugal with how I spend it, and since I wasn't doing much end game stuff I didn't have to worry about expensive repairs. The Marketboard has long been a total mess thanks to undercutters, but I'm pretty certain that's not exclusive to Leviathan.