Like others, I would like a .45 carbine. I wish Beretta would update the cx4 storm design with a premium model with an aluminum fore end with mlok slots, a little less plastic all around, scrap the built in sights for a rail, and design a magazine that can hold 10-12 rounds flush and some extended 20 round mags. They used to make a .45 in the CX4 Storm but I think it held 8 rounds or something like that.
I would also go for a Ruger LC Carbine that shot 9mm, .45, or 30 carbine. I love the design but I’m not really interested in the 57. Better yet, Glock do something like the LC design and start making carbines.