how tall do u believe your arm should go in vex gateway with a NZ design?
“It’s over 9000!”
But seriously, probably anything above 30 in. is good. It’s sometimes nice to give the design more vertical reach than necessary (2 to 5 inches extra) just because it gives you some “wiggle room” for incremental design changes and height sacrifices made in the build process at little to no cost for robot function.
It’s odd to have this conversation with less than 6 weeks till worlds. Are you thinking of starting a new bot?
Dude if i cant put my preloads then all my interection zone autonomus have to be changed. 
make it like 34" so its easier to come down on a piece to descore… are you gonna try those fold down intakes for the descore? good luck at worlds!