You should absolutely check out the Beretta PX4 Storm. Originally designed for the .40, the rotating barrel design really helps tame the cartridge. They come in DA/SA, DAO, and a unique Type C that mimics a strike-fires pistol design. That’s what I have and love it. The other recommendation I will make is another Beretta actually. The APX is the most shootable, ergonomically designed pistol I’ve ever held. I have it in 9, but it also comes in .40. Highly recommend it. .40 is a great cartridge. Similar ballistics to a .45, with usually 50% more capacity. I don’t view it as a “middle ground” between 9 and 40. I see it as a modern update on the .45 concept.