I'm not even fully done tweaking my prusa i2 yet and I'm already wanting a bigger and better reprap lol. I would love to modify or even have a second machine.
In all honestly some of the things I've decided I don't like about the design and it very well may be trivial but I want a 12x12 print bed. I also feel like the frame needs to stay out of the print area. I will probably never exceed a print height of 150mm anduld probably give me trouble if I did but if I wanted to try I feel like I should have that option. The last thing I think needs changing is the print bed comes too close to outer frame rail that keeps me from being able to take advantage of the full 200x200 print area unless I want to flip the smooth rods up and sacrifice more vertical space. The design is great not bashing the design at all but the frame limitations is what throws me off
Would like some input or suggestions on how u may have improved upon or built after ur prusa