See here for a comparison:
Speed of DirectX11 over Vulkan is almost twice as fast when compared to OpenGL and the power consumption is a lot lower, too.
The author is being payed by Valve Software. So this is likely the more faithful implementation, probably the best you could ever hope for. I don’t like how it’s a set of DLLs and that it wasn’t put directly into WINE, but this is just how it is now.
DirectX12 is also being worked on for WINE and while it, too, gets rendered over Vulkan, is it a part of WINE’s source code unlike DXVK. There is no DirectX12 over OpenGL implementation from what I’ve seen and don’t think anyone would want this. Vulkan then is available for Nvidia and AMD as well as Intel on-board graphics.
There is Vulkan for Android, which lets players run WINE on their mobile phone and means they could play EVE Online on their phones.
The system requirements don’t increase necessarily. You’d still have to use WINE, which means you’ll also be able to run with DirectX9 and X11 over OpenGL. Only Vulkan is the way forward and what people will want, but it’s not somehow exclusive. It would be an optional feature to have with OpenGL always being available as fallback.
Your problem will be that when you don’t add DXVK straight to it, then why should people use it when they can just get it all over Steam and all inclusive? With Steam you get EVE news and special EVE offers, you can play other games with it, and so forth. With Steam do players get to use the Windows launcher and they can be certain not to be using any software that is somehow different from the Windows version. It’ll be difficult to see an advantage in using a Linux-native launcher over Steam when it isn’t at least on par with the Steam performance.