I tend to run my Dunlop & Federal pairs together @ 40 psi. At that tire pressure I highly doubt there would be any difference, especially with both pairs being so worn down. I wouldn't doubt a new Dunlop may roll easier than a new Federal, Nexen, or Kumho tire, but tire pressure may be a factor to a point. I haven't seen a study showing over inflating does anything to improve fuel economy. So I don't see the need to go above recommendations on tire sidewalls, but I do ignore recommendations on car door stickers. Not saying that's best practice. I just like more air verses not enough air.
There's some science that proves/shows a wider tire will have less rolling resistance than a skinner tires, too. Bike tires for the Tour de France have gotten wider in recent years for that very reason. Without using pics - a wide short patch on the road may have less rolling resistance than a long narrow patch on the road surface. This would account for Top Fuel''s great economy numbers with wider 15" LRR tires. Along with LRR, bikers are getting a smoother ride from a slightly wider tire. I am not supporting these claims here, but anyone can check this for themselves.
I value the skinny tire, because I just know it's superior in snow. Especially, when climbing hills. I also like the tiny Mirage tires. It's part of the car's charm. Then again, I drove a car with 12" tires for 14 years, too.
I do think the Mirage should come with 175/65r14 & 185/55r15 factory tires, because these two sizes are an identical 23" in diameter. They are very common sizes, & almost all tire brands carry them!
If money is not an issue & you don't care how often you need to replace tires, 165/65r14 Dunlop & Bridgestone tires are the way to go. If you want more life out of your tire @ a much better price, I really feel Federal, Nexen, & Kumho are a good place to start. It's too bad the new Falken tire has a lower rating. Otherwise, I would include it in the mix, too. I am just glad we have a few more choices now.