Hi !
I also wanted to start an open source project for this purpose, but wow, you were faster! 
Ok., maybe we should do it together.
My goal was exactly the opposite. High performance, positioning in closed loop with field vector etc...
So we have 2 different needs, an I think they need 2 slightly different hardware:
- High precision positioning with encoder (ttl or sin-cos with interpolation) and closed loop operation
- low precision with no encoders, but some phase monitoring sensorless loop, for flying and RC application or only speed control
We need in both versions a good current loop, that is using some kind of current sensor, that is cheap and fast.
I suggest to not use SMD mosfets, since those can only be difficultly replaced if burned, and wastes precious PCB area, and heat transfer is not provided accurately.
My goal is:
Imax peak = 25A
Id = 15A
Umax= 80V
I have already used a very neat type: IRFI4321PBF-ND
It is cheap, and can handle 150V and 34A continuously. so it is protected against HV ringing and spikes during PWM switching.
And it is fully closed package.
As current sensor we should use 2 pieces of ACS714 +-30A
I want to use KiCAD because it is free etc.
Suggested communication protocols:
- serial
- step-dir
- CAN bus
- USB
feel free to contact me and lets do it!