For the output module, why not looking at a mixer+out+headphones out ?
In fine, you might end up with several voices when you'll get another vco
I started with a 4ms listen four and i replaced it by a XOH (with a XPAN before to increase the XOH limited mixer capabilities and save space)
The Quad VCA before the Out will do the job in the first time but as your rack will grow out, the needs of VCAs as well
However listen to the pro, I am still a beginner
-- anglr

Finding the right combination of Outs + Headphones + the features you want can be tricky. In my search, it was "not enough channels", "too expensive", "not enough sends", "no mutes", "too big", etc. Those features are nice if you can get them on your mixer. But I wouldn't make them must-haves if you find something that works for you.

Another factor is performance. Some mixers are meant to be set-and-forget. Others were purposely designed with performance in mind. That's something to always consider when buying a module... ergonomics are important if you're going to be playing the module live. Perhaps something not towards the top of the list when you're first starting out. But, something to consider if that's a goal.

Cheers.