Those circle-based caps /C/G/O/Q/ look very wide, especially /C/. I guess the commitment to geometry is a constraint there.
Speaking of which, does the hard geometry of a structure like /Q/ argue for a single-story, round /a/?
Stroke width seems uneven in spots (northeast to east of /D/, southwest of /C/c/, south of /U/, south to southeast of /g/...)
/s/ looks a bit wide.
I quite like the figures! That form of /6/9/, with its straight-to-curve transition, can be hard to draw well but you have here. Look to achieve that same success with caps like /J/.

I’d interested to hear your opinions on this. I’ve been sketching on an off for a while, but I’m not sure if it’s worth the effort to finish it. There are plenty of geometric sans serifs out there, particulary the grotesque-ed geometrics.
(PS: You might notice the vertical proportions—enitrely nicked from Helvetica! I’m not posting this as something I intend to release in its present form anyway, so I figured it might make for an interesting conversation. Is it OK to reuse vertical metrics?)