Until you gain more experience, I would recommend against it.
I shot myself in the foot "shortning" the wires on my first build.
I had hidden the controller under the seat and while it was totally out of sight, but I had to stuff the assortment of "cheap kit" connectors and extra wire into a camera case and I didn't like the look of that.
Rashly, I started clipping the connectors, only to find that I needed to learn what connectors I wanted to use, then get them and various accessories and tools ordered, etc. I got side-tracked and when I got back to it, I had forgotten where all the "rat's nest" of wires went. That controller was somewhat unique and I couldn't find a diagram, so I was trying various combo.s when I fried the Hall sensors in my motor
This time around, A little wiser, I'm stuffing everything into a small mesh handlebar bag.
Even though I am now more versed and supplied with connectors, etc., I'm not going to mess with them until I'm sure on the final configuration. Which motors, controllers[I have a bunch now], controller locations, etc. Depending on which controllers I settle on and what features of the C.A. I end up using is going to change some things, I'm sure. I may even want to "beef" up some phase wires which would be the time to re-do the entire harness.
I am assembling and testing this week and should have some pic.s towards the end of the week.
Can you coil the extra wire up and pplace it the frame bag for now? Or does the controller location prohibit that?