Everybody has their own preferences and it's all part of your personal pursuit of what you think is, or would be, ideal for you. I have the feeling you would appreciate any Alembic that you spent some time with and be able to make great music with it.
CVS vs Q-switch? I have 2 fretless Series I basses and 3 fretted Series IIs. On the Series I my Q-switch on the bridge pickup is set to the middle position with the filter wide open - for just a touch of ultra high-frequency boost. On the Series II the trim pot on the bridge pickup is set for only a slight bit of boost on the high pickup for the same effect. That extra tippy-top boost is extremely subtle, especially if I'm playing with any other musicians. Pickup volume and filter controls remain wide open and these are the settings I always use, nothing ever changes. (Although I admit I may be odd in this way.)
For your custom build Alembic can literally do anything you can think of. Decisions about wood, body shape, inlays, LED colors, electronics package, jewel encrusted backlit logo, etc... are all part of the joy is making it your own creation. You choose all the options that appeal to you.
All I'm really trying to say is - in my experience, I sound just like ME on whatever bass I pick up. The details can make a difference - to me - but rarely can anybody outside of my own head hear anything but ME playing. So in my opinion, the difference between a Continuously Variable Q and a Q-switch is way out there at the extreme end of consequences.

It puts the Q in subtle.
Jimmy J