Throttle smoothness on EU Z900

Hello!
I own a 2022 EU Z900. My main goal of getting a ftecu flashing kit was to reduce throttle twitchiness to make the ride more smooth when re-applying throttle. In stock form the EU version is very twitchy - especially at lower RPMs.
I was hoping just disabling "deceleration fuel cut" (and no other changes) would fix this issue, but it did not.
I then applied the unrestricted image ftecu provided for my ECU and it definitely got a lot smoother. And I think I could even smell that the mixture got richer.
I have also read that the EU Z900 has too lean mixture by default and disabling the O2 sensor would make it use a richer map, but I have yet to try that combination (disable decel fuel cut & O2 sensor).
Since I have stock exhaust except the slip-on, which is basically a straight pipe, I'm not sure if running the unrestricted flash is a good idea. Any downsides to it?