I'm definitely going for the Nitron NTR R1 without the Nitron Hydraulic Preload Adjuster, that's way too much and considering our type of bike there's no need for it. As far as forks, since changing the whole interior for a cartridge kit is also too expensive I think I will change springs for a stiffer ones, keeping same SAE oil though.
after several month of waiting for delivery, I got my suspension upgrade installed (ohlins stx46 for the rear and Nx22 cartridge kit for the front)
Not cheap but no regret. The bike feels safer, especially on bumps or while braking, without loosing on comfort.