H6D-75c or there abouts should be launching in the next 3-4 months. The H6D-50c was really a crutch to get the back components up to current spec's with CFast, etc. Doing the next gen 33x44 on a full H body is easier than the X2D form factor. Plus, it allows folks with the X1D to enjoy their investment at current pricing instead of having it discounted already. The trick is going to be the premium associated with an OVF on the smaller H6 chips. Is it more than $3-4k?
CPO on the H6D-50c is already 12-13k, and the H5D-50c's from 8-10,500 depending on wifi.
My biggest concern is keeping the volume of H bodies & glass sold high enough. We want a new 35mm prime, and something like the 75-150mm zoom would be amazing. But does Hass & Fuji keep the investment up? The new 1/2000th shutters are amazing, and fast enough (maybe we'll get a bit more with a EFC, but I don't need it). The only other issue I can see is the challenge of focus, when dealing with a lot of depth near the focus point - 100mp+ totally tattles on you if you don't nail it.