I still like "Dayna Rain", for the reasons I gave back in October: http://www.behindthename.com/messages/13783.html
But I'm starting to prefer "Adriyanna Marie" now, for the following reasons:
1. "Adriyanna" is an anagram of Diana/Ryan.
2. "Marie" is already your own middle name. So this baby would have two of your names and only one of Ryan's -- signifying that the baby is two-thirds yours and only one-third Ryan's because you're shouldering most of the responsibility for her right now.
3. "Adriyanna" sounds a bit like "Arianna" -- a name which you're already considering -- except that "Adriyanna" isn't as common as "Arianna" is right now.
4. "Adriyanna Marie" has a nice flow and rhythm to it. It's pretty and it rocks. :)