We katana upgrades

[scombat]

Afternoon all

I have a we katana (l119a1) I haven’t actually played or used this for many years. I am getting back in to airsoft and was wondering if anybody could tell me what’s the best upgrade parts to use or even if it’s worth while.

I have already installed the following before I stopped playing.

Rotary hop unit (I can’t remember the brand)
gates nano mosfet active braking

thanks all