I started a new game in 1.5 as muscovy, after a hiatus playing CK2, to check this new AE. At this moment, I feel the AE has been well executed by paradox: first war with novgorod, and I get about 78.5 AE with them (I took 100% worth of WS in provinces, to release the biggest finland).
I had annexed Tver beforehand with minimal AE: 11.2 and I had allied/RM Poland.
Novogorod subsequantly forms a coalition against me, and sweden goes from "friendly" to "outraged" with -30 relation, I quickly dispatch a diplomat to stockholm.
No one else joins the coalition (maybe it's because sweden and lithuania are still under PU and can't join by themselves? That would be a nice exploit): no hordes, not the livonian order.
Second war with novgorod, I snatch the rest of the territories and novogorod is now left to one province (novogorod): another 50 AE.
During the peace time, sweden had gone back from outraged to friendly +50 with my diplomat, poland is still allied and "cordial", denmark and lithuania have rivaled me.
Ryazan joins the coalition, which looks pretty normal as they are my closest neighbor, still no hordes, no LO, though I have generated about 130 AE total.
Third war with novogorod, I take their last province. Ryazan is still in the coalition against me.
I end the game here as I have forgotten to guarantee ryazan again after the last coalition war (novogorod-ryazan) and the golden horde is attacking them.
All in all, it looks fine AE wise: countries which are friendly don't join coalitions, countries which are far away don't join the coalition.
I'll continue this game tonight taking care of the hordes and see the results:: ie will the ottomans or timurids join a coalition against me if I beat up Kazan (normal (and painful) behaviour in 1.3.x games)