When I made my mount I gave serious consideration to going Alt Az instead of EQ as Mel Bartel's system can do this with field de-rotation but this required another servo controller and servo to do this plus modifying a focuser to move rotate meant more weight at the end of the OTA.
One of Mels servo controllers does 2 motors so if using 2 controllers you have both drives and focuser and focuser rotation covered.
I went EQ instead for the simplicity , but if i were to do it again with a larger scope I would go Alt Az due to the smaller foot print inside an observatory.
Some thing to consider.
Have included a few pics of Mel's Servo system.
Waiting on drive and idler rollers to be made for the friction drive .
In my procrastinating about making a mount I toyed with the idea of making a stepper system but my patience is not up to that task and hence I used Mel's ready made servo system with the excellent software he has written for it.
My other consideration was integration into charting software and ultra fine tracking with out PE and fast slew speeds.
His stepper system can be bought in various stages for price reduction.
As far as drive reduction goes you need at least a 1/2 to say 1/10 arcsecond tick size or smaller to get pointing accuracy and tracking.
The sky is 12960000arcseconds
My system works out around 1/3.with a total friction drive reduction of 2200:1 and enocder ticks of 4 500 000
I can still slew at around 6 degs /sec with the servo's which is more than fast enough..
The tick size is the encoder on the motor or shaft that is used for positional info.
The smaller you go the more accurate but the slower the slew speed is going to be with a given motor .
If your not worried about positional encoding but just driving then you could get away with less reduction as long as there is sufficient to smooth the steeper pulses.
Hope you have some fun with the project.
). But it is possible, and it'd be very rewarding once accomplished. 
