Looking for choosing a permanent airline between Delta and United

I'm in an odd situation with where my home airport is (PIT). My wife and I fly international at least twice a year (mainly to the Asia and the Philippines to visit my inlaws) and I'm trying to decide what airline I should just permanently stick with because prices usually end up the same for the most part.

On one hand I have a Chase Sapphire CC and theres a direct flight from SFO to Manila (tho we prefer Cebu but we take what we can get). so points/ that other stuff is easy.

On the other hand the CC points top out for me fast and I could just roll with Delta and the Amex. The other thing is the million miler status, from before I met my wife I currently have 55k in miles while on United I'm hovering around 18k.

So I guess looking for an opinion on what any of you think might be a better option. Clubs aren't that big of a deal, we care more about value/comfort than anything. The majority of the hubs we fly to get us to the destination.