I think it depends on purpose and jobs to be done with dock. I see multiple options:
Portable connecting hub: actually can go without eGPU and I would probably vote for max portability, so I can take this dock with myself anywhere. Actually it is more like and adapter than dock. Something like this - http://www.dell.com/en-ca/shop/dell-adapter-usb-c-to-hdmi-vga-ethernet-usb-30/apd/470-abqn/pc-accessories
Traditional dock. Here are two options:
a. Just connecting hub - pretty ok for most users but should have really good price. It is for those people who have one monitor and some stuff to quickly connect when at work or home.
b. 4k monitors connecting hub - if we want to provide 4k monitors connection I expect we will need to have some room for eGPU (probably build in). Acer has made some of those docks https://www.notebookcheck.net/Acer-Graphics-Dock-with-Nvidia-GTX-960M-Review.175429.0.html
I’m not sure if it is really viable option as not so many people I think have 4k or dual 4k monitors setup. I think it is still niche. We need to make poll to understand if it is needed.
c. eGPU - eGPUs like Razor Core can be used like dock. Could work, but only for those people seeking eGPU solution. Will be pretty expensive. I’m not sure that this is good option for dock, because of price for most people.
Summing up: if we talk about dock, the decision to go eGPU or not depends on those 4k monitors support. If community need it than go with this. Otherwise - non eGPU still be good option.
As for me making eGPU like Razer core - should be done as another project as there are also multiple options.