The major difference is in the AA choices, which in EQ1 you HAD to get GROUP/RAID AA...choices that EVERYONE got. The group leader had to have target of target in EQ1...that comes standard in EQ2 without AA.
There are very few AA that every class has access to. These are the 'general' AA in the Sundered Frontier line (harvesting, mana pool, food duration, etc). Instead all the AA tabs are class/subclass specific. So there really isn't a need to have 1500 AA. I'm sure OBD or someone will give you a more detailed breakdown.
But like Nadenu said, once you get over 200 AA it does seem to take a lot longer to get those last 50. My main hit the 250 cap a few months after the last expansion was out..being a solo player who groups every now and then (and raids even farther in-between that). Once you reach the cap you will find that you won't need to, or even want, to have every thing filled up. As you grow you will no doubt change it many times around until you find a setup that works well with your playstyle and class, but once you do you should notice that 250 is a very good amount to play with.
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Things I sometimes play...
"What do you want to be when you grow up?"
"I want to be a unicorn!"
"Awww, why's that?"........
"So I can stab people with my face."