What upgrades/accessories do you recommend for my Tippmann A-5? *Plz Read Description*?

I have a Tippmann A-5 paintball gun and have been attempting to upgrade it. My mother bought me the gun as a basic A-5. While the cheapest way to get most of the upgrades is to buy them with the gun, I might as well work with what I got. I am basically certain I will buy a Flatline barrel, but there are a couple other upgrades that I don't think i'd really need or use. However, maybe i will get some of them just for the hell of having them. If it helps in shaping your opinions on the following, my gaming style is geared more to woodsball and scenario games. Although I am able to play airball/speedball and must as the game of paintball is being taken over by this faster tournament style of play, I prefer woodsball.

Please give me you opinion on buying these items for the Tippmann A-5:

Stock (probably wouldnt use much)

Nitrous Tank (currently on CO2. From my understanding there is no adjustments necessary to make the switch?)

Red Dot Sight (probably wouldnt use much)

Any sort of new hopper (from my understanding highly unnecessary)

Air Remote (probably wouldnt use much; would need to buy new pod pack also)

Any others you might be aware of.

*Thank you for your time in reading the previous information and writing a response that will help me upgrade my gun*