Welcome and congratulations! Post up some nice pics!
Whether adding HFC will be enough depends on your personal preference.
For those I would check out the Berk and the ERZ.
F.I. are making a great exhaust (ps. F.I. if you read this, this is coming from a current 350 owner, so there is some love for your products from the 350 group
)
Stillen G3 seems to be a popular choice as well, but also make sure to check out the Injen.
As for the other items, I would have a read around the technical section of this forum.
There is too much information to sum up in a post.