I finally decided to buy/build/hack a proper lightsaber. I went with one with:
Luke's replica with proper thin neck
neopixel blade for more realistic ignition and shutdown effects.
open hardware and open source effects board (proffieboard v3.9 with proffieOS 7.7)
I couldn't find one with all these features. I found one with the right hilt and blade, but with a Xenopixel board. I bought this, and replaced the Xenopixel board with the proffieboard v3.9