Each of those new models will appeal to somebody and they'll likely sell well ..... most Glocks do.
I've been teaching people to shoot Glocks since the late 80's and I can tell you the double-stack models don't "fit" a fairly significant number of people with average to small size hands. Thinner guns are simply easier to shoot well, so these options are welcome additions to the line-up.
It's like Glock is now trying to compete with Kahr and the single stack line they've had for years. The Glock will be more reliable than the Kahr. I like the slide color change, but I agree that the added 4-5 rounds (depending on if you top off) to me doesn't validate changing if you currently have a Glock 43. With that said, it will sell for Glock. There tribe is strong and loyal.
You know I was on the “bash the Glock 42” and “where is the single stack 9mm we’ve been waiting for Glock?” train. I’ll have to have some salt with my crow, because like you I love, love, love how the Glock 42 handles and carries. It’s a sleeper if you discount the .380acp, but I can put them on target fast and accurate. They’ve finally got down enough in price to warrant a purchase.