i actually had a few thought about printing speed and accuracy some of my ideas will definitely break the 100$ barrier but maybe something for a pro version?
OK so here are my thoughts i would use a peristaltic pump instead of the drip system.those pump are inexpensive easy to make and can be very accurate (probably more accurate that the drip allowing more control over z axis and no wasted time waiting for the drips) i imagine you could even use the drip system as a bootstrap and print the pump yourself.
i was thinking that if you use a floating base to limit resin use and focusing issue you might try to use the electrical resistance of the saline to get a very accurate feedback on effective water height (z axis)
maybe the use of low power supersonic transducer can solve the problem of the resin not flowing fast enough. you could induce microscopic "waves" or a kind of surface creeping to speed up resin flow onto the object
maybe you could investigate the simultaneous use of multiple peachy to speed up bigger objects (each peachy printing a part of the whole at the same time)
i have one last idea which is kinda "out there" don't know if its even possible but how about using some kind of maglev technology to suspend the mirrors (no wear and tear because there are no strings and possible even reduced resistance to movements)
keep up the good work everyone ..