Despite new versions of Aion always bring something new, the fact that 4.8 was so bad recibed is that Katalam is missing., it is a good PVP place and people love it, Signa and Vengar didn't had that appeal, myself that I am not a PVP player I can give note of that, doors and guardians keeping them is just nightmerish, you are so constrainted to a place that it makes easy for the attacker to get hunted.
Bloodmedals are harder to get because the only way to make them is Akaron garrisons and their legates were the hell fuck hard and to make things worse, only some missions pop up if all garrions form a cardinal point were taken, even to add more salt to the wound , balaurs retake those garrisons quickly than we can.
Sure, it can be fixed somehow, like I don't know, a custom mission that gives a fair shake of BM or reducing the prices of the set.
The content is also debatible, sure, Makarna was hellish, but besides of that.. it dosn't bring anything new, only Makarna, a place where few people could beat it.
Sieges get hit hard.. Abyss, Ingguison/Gelkmaros and Kaldor .. Kaldor have a interesting mechanic but requires a bit fair shake of people, to hold 3 garrisons at the same time and deal dammage to the boss, nobody nowadays is interested on attacking Inggison/Gelckmaros forts (But I think we can agree that we can ask make those forts give GP points and ceranium medalls, but that honestly didn't work well on retail Hellion)
I don't think much people have a issue with their skills, sure, stigmas are reduced and the 7th Stigma may limit a bit your play, right now you can play as whatever you want.
And on this version there is autolearning skills, the only thing you need to concern are the stigma level skill