Differences between live and P99/classic

[Hroth]

What are the major differences between live and P99/classic EQ in terms of the TLP servers? I haven't really played live since around something like 2006.

With the announcement of the new TLP server, I'm considering subscribing for a month to check it out. I know some classic zones have changed like Freeport and Nektulos. Is there any other major zone changes? Is Cazic Thule 2.0 (the zone) in as classic content? Do mobs only last for 3 seconds in zones like solb and lguk due to overpopulation?

I've heard mage pets are pretty OP. Do they trivialize the content so that groups don't want anything else? I'd be considering playing a paladin or a ranger. Are they even viable? I know spells got revamped as far as what level you get them. Are there any other classes that dominate?