Hi Eonblue77,
How about going to a hotel room and playing around with your modular rack and using headphones, shut yourself off from the rest of the world and enjoy modular synthesizers? ;-)
But I guess that's not really what you wanted to know, "where to go with your rack" :-)
Okay then, regarding your rack, the size is kind of okay I think, for starters. It's good to keep some space free, keep roughly one row free, if possible a bit more because you will see that you need that free space in the (near) future. But that's what you already did, so that's good!
You might consider one more VCO/DCO, perhaps an EG more too beside the Maths? What I completely miss (or did I overlooked that?) are LFOs. Didn't really see them, not as such at least.
How are you going to "output" your sound from the modular rack to the outside world? An audio I/O module would be helpful here, if you take one with headphones output you can use your rack with headphones too (to go to that suggested hotel room). But of course you can use headphones via your external mixer too (that's what I do and feel is most practical but that's up to everyone's personal taste of doing things).
Good luck with the planning and have fun with modular :-) Kind regards, Garfield Modular.
For review reports of Eurorack modules, please refer to https://garfieldmodular.net/ for PDF formatted downloads