Nah. Delta's brand identity is actually very well done, especially when compared to the 2006 era Delta or NWA identities. (Being ex-NWA, the silver livery and shortening to NWA was always sort of meh for me, I was a big fan of the 90s bowling shoe red scheme... and on the other side of the aisle the sans serif Delta typography always seemed dated to me from their old identity.)

If I recall correctly from some article I read, the identity work was even done internally by a team within Delta, which is really very impressive for a company primarily focused on a non-design related industry. Typically branding/identity/livery work would be outsourced to a third party that specializes in it - http://www.wolffolins.com/ Wolff Olins is an example.

I think it's fair to say the livery (hideous as it is) isn't the only concern CO/UA fliers have right now. My 1K friends are very, very worried about how CO's top tier customers will integrate in, and they're also very worried about the impact of UDU with a larger pool of elites and smaller F cabins than NW/DL has. They're also super concerned about getting stuck on ex-Continental aircraft that aren't configured with E+ (or, heaven forbid, the combined company dumping E+ entirely.)