Leave the rifle alone! Before spending money on a bunch of mods, spend your money on ammo and go practice, practice, practice. Learn good breathing and trigger techniques. Annotate your target with date, range, conditions, ammo type, etc. and keep your targets. Note your progress. When your rifle is fully broken in and you're familiar with it and its characteristics and have good markmanship techniques, then begin thoughts of modifications. Equipment cannot make up for poor technique.
Just my $0.02 worth