How about this as another choice?
Choice 4
Canon C200 (A cam) - Many clients love the canon color and find it to be quite pleasing, plus canon cinema cameras just scream professional for clients in general.
Sony FS700 (Slow Motion Cam) Treat this as a specialty cam for slowmo, you can get 2K DCI 240fps if used with an atomos recorder for very cheap, not to mention the in camera burst.
Panasonic GH5 (B Cam) Great all rounder that can be used in most situations, just not great auto-focus and you already own it.
Pros: You're covered in every aspect, you can have the C200 to please clients and get the best autofocus on gimbals, the FS700 will get you some of the best slowmo under 10K and cost you around 2.5K and you already have the GH5 as a great all rounder you can take into every little corner and get a great image.
Cons: That's three different color sciences to deal with, while I personally don't think this is much of an hassle, some might struggle with it. Also three different mounts but sticking with EF lenses and using adapters on Sony and Panasonic shouldn't be much of a problem.