Some things I wished for after I completed it:
1. Another covenant. I realize it was in the past and that technically it was the Forest area, but maybe an Oolacile Covey would have been cool.
2. More NPCs with which to interact. Chester was ok, but really only served to hand over his top-hat when I killed him.
3. Some distant relative of Havel. After killing the dragon, I'd hoped the tower would be there near the cliff, but alas it wasn't.
1. Who was the lady paying her respects at Artorias' headstone after the battle? Alvina in human form?
2. What is the best type of weapon to damage the Guardian? I tried lightning and fire, but neither seemed to do much against him. I only beat him after I summoned 2 helpers.
3. Just before you get to the elevator leading to the bonfire before the Chasm of the Abyss, what is that thing that attacks in the room with all the statues?
Overall, I was happy with the DLC. Some more trophies would've been nice, but that's just nitpicking. It certainly wasn't short on boss battles and I ended up getting 1 of the special tail-cut weapons (from the dragon). And I got Gough's GreatBow, but the damage seems really low so I doubt I'll use it in place of my +4 Darkmoon Bow.
I didn't try the arena area because I'm just not that into PvP.