A desktop PRO3 would also sell quite well... They could further cut the price by removing the cv stuff and three controls and even the extra midi out for that matter.. I bet many would really want such a synth for their allready crammed desktop space.
To me the cv part is overkill... The synth in itself is so powerful and capable, I dont even know what I would want to connect... Yes, it is a cool eurorack controller, but way to expensive just for that...a keystep pro would be a much more go to solution for that.
The problem for me regarding pro3 and eurorack connection is the lack of preset saving... The pro3 has full preset functionality, but as soon as you introduce modular stuff into the chain, you preset saving gets screwed up with some things saveable and others not... If I was to add modules myself, I would probably end up with analog FX modules, but then I would have to get two of each or spoil the pro3 stereo signal path... Its just that no matter what I think up, I feel that something gets compromised.