I have a number of Dark Ascension packs that I'd like to trade for singles, but I wasn't sure is this was allowed here. Could someone please let me know if this is okay?

Hello,

There are no rules defining what exactly you can trade, but there also exists no functionality that would help you trade things other than cards. :)

But if you know someone actually wants packs and you can talk to them and agree on the trade chat, it's perfectly fine.