Yeah, that's what I figured. I primarily use the Business Preferred for all my business spend at the moment, but later this year I'll apply for the Unlimited for the 1.5x points on my regular expenses. Phone/Internet/Staples on the Cash card, and travel/postage on the Preferred. I also have the Sapphire Preferred, but that's going to sit dormant for a while, I think. I don't carry a balance on any of them.
To me the case is clear for the Business Preferred, but honestly I'm asking for a second opinion about using the United card for the airfare purchase. Am I seeing the big picture or focusing too much on the Unlimited Rewards points and maybe missing something else?