Personally, I think you are comparing apples and oranges. If the routes you typically fly are on US because they are cheaper, you need to compare those costs to other airlines. It seems you already have. On the other hand, when you venture out and check the redemptions, you have found that on THAT route, US is not such a great bargain, which must be because the paid ticket is too high, in comparison to the other airlines you have checked. What about other potential redemptions that you a interested in?

It's not a one size fits all kind of thing. There is not one airline that will fly you on paid tickets for the cheapest all the time and then, have the best value on your redemption. if so, everyone would fly that airline exclusively and there were be no availability for redemptions...This is why people tend to have miles in several programs, more opportunities.

In terms of your personal situation, the Barclays card could help with status if you spend enough. If you don't care about status, then did you look at SPGs airline partners and transfers? Transfers in blocks of 20k with bonus? Have you considered using your CCs as an opportunity to diversify? I'd also consider flying US but crediting to UA and pairing with Chase URs. If your typical redemption will be four people, have you looked to see which airlines are good for families as many times, you find two seats, not four.

You may also wish to tell people where you are based as the people similarly situated are probably best suited to help you. I'd also recommend that you figure out what it is you are looking for. With a clearly stated goal like family of four to X in Y class, it will allow others to refine their suggestions as certain airlines are just better for redemptions to retain locations.

Good Luck!