Well, there is also the Moto Z Droid Edition, not just the Force. I think it's a bit thinner and lighter.
At this point qi charging is no longer important to me. The only plus for me is less wear on the physical port, but I think that's less an issue with the USB c connector.
Lenovo has said that mods will work with future versions of the Moto Z models, so presumably there is some future proofing if you are sure you are staying with the Moto Z line.
I still can't buy a phone this physically large (I don't care how thin it is), and this phone is way too expensive, knowing you'd also be buying a mod. Never mind that Lenovo's support for last year's models has been atrocious.
I agree - I think it's possible we'll see a phone like the Maxx 2 later this year, but it'd be lower end specs. The Z models are this year's high end Droids.