what no engine? Seriusly, to my eyes AO always was a good looking game. So no problem here.
Server merge is the most important change and gladly its comming.
NPE probably the second greatest issue, incoming, yaaay! New blood is fun, but being new isnt for most people.
Brings me to system changes aka rebalance. The only AOs strongpoint is gameplay. Why is rebalance away from main priorities. For sure it must be easier than engine, yet in many ways it improves the playability more.
And as for engine? Not a priority for me, someday it will come and after a few days we'll complain about aimed shot again.