To lighten the rifle, lose the bipod and install an aluminum lower. Aluminum mags are a help, but HTF right now.
If you will ever want to use a scope or other optic, consider keeping the OEM buttstock, which raises your eye leve in comparison to most other styles.
A para rear stock will add weight and complexity to your rifle, while possibly detracting from reliability. Unless you have a compelling need of a folder, don't.
SAW pistol grip is good, better angle of the wrist, and more natural.
Your rear sights are calibrated for use with an OEM length barrel. As you shorten the barrel, the sight become less-well calibrated. Your call, but I wouldn't unless you have a very good reason.
Install a shorter muzzle device which won't shorten the rifle much, but will take some weight off the very front end. Lose the metal handguards and go with quality synthetic.