I don't think equating the Arbor Wilds with Denerim or ME3 ending is legit - you get the same cut-scene regardless, and it doesn't include any of the choices you make (mage vs templars, grey-wardens vs not...well, those are the only choices -.-). You get a little bit of that when you're at the camp (e.g., Briala can help you if you helped her), but otherwise it's basically identical.
ME3 very clearly showed your allies as you had them, and Denerim gave you the option of fighting beside them. Also it used all of your companions and showed why they were needed elsewhere. At the end of the Coryfistus battle, I LOLed when I saw all my companions show up after he was dead. Thanks guys!!! I knew I could count on you................... Also, their absence means that there's no consequence to you getting a lot of approval from them or just enough to keep them from leaving, etc.
The battle itself was pretty meh. I mean, the Coryfishies battle in Legacy was the shiz and actually kind of scary. When Coryfinnish randomly brought the Temple of Sacred Ashes into the sky, I was like uhhhhh why did you not do this before ever? Why wait until your entire army is decimated? It was all just very weird.
I didn't mind the after-party, it was a nice gesture toward the end of DA:O.