So I'm considering upgrading the stock on my rifle. For those who aren't familiar with this model, it's a .308, 18" heavy barrel, accutrigger, detachable mag, with bolt release on the trigger guard. It does NOT have the Accustock.

What I'm looking for.
I'm wanting to avoid wood and excessive weight in whatever stock I get. I'm looking for a tactical look. I haven't made up my mind on thumbhole, pistol(ish), or traditional style rear grip. Being adjustable would be nice as well. I'd like to stay under $350, but am keeping an open mind on budging a bit off that.

What I want to do.
I'm an amateur wanting to get better at precision shooting. Right now at 100 yards, but want to work my way up to 500-600. Won't be doing much free hand, mostly bench, maybe some prone shooting.

It seems with the heavy barrel and newer style action with the bottom bolt release limits my options.

My questions.
Is it possible and/or worth it to have a gunsmith improve the factory stock?
Will Savage sell me an Accustock and would that be a good option and how much?
Any input on different style of rear grip?
What specific recommendations do you have?