|Tarq fighting a Terranite|
One very small detail in the 4144 client made me switch back to it - the display of how much damage has been done against a monster. It's a detail that doesn't really matter against weak monsters like fluffies and pinkies, but is really nice to have when you're facing Yetis, Terranites, Fallens or Jack'o. It's a small detail I'd love to see in the official client.
I didn't get a chance to test the stability of the main client on the Auldsbel server. The last time I used the official client it froze on my end when I logged in as GM and entered an area players were. I confirmed this behaviour several times.