1. No A circle Pad Pro is not required.
2. I have not tried modding a gamecube controller, but the 3DS controls work fluently and the touchscreen buttons are nice to have IMO.
3. 1.0 is perferred to acess all the glitches including gibdo BA. If you have 1.1 just go to the Eshop and uninstall the patch.

Happy Speedrunning :)

Thanks for the reply! Looking forward to running my favorite game. :)