Big Pimpin', you just posted the two most controversial mods out there for Zips.
I wouldn't really reccomend either one of these. The no reverse mod only helped a little. For the work it takes to add a switch and place it so it looks good, would not be worth the results. This last mod you posted is believed by some to be a hoax. I'm one that agrees it may be a hoax. Invented up by a bit lover to take a few Zips off the face of the earth.
The resistor jump did absolutely nothing for me. "A lot" of others have said the same thing. Have you tried any of these?
The only Mods I'd suggest would be the PCB swap. That's a must if you ask me. It does everything the two mods you posted above are supposed to do. Increase the power to the motor. Second mod would be the Dual batt. And that's only after the swapped PCB's with a clone. After that, the only mods you'll need should be cosmetic. Find new bodies, paint your old one, lower it, raise it, add decals, etc... If someone still feels the need for mods after those three above, throw in an extra motor.
Of course, everyone should do the antenna mods.