I get all the cardboard boxes I can use from construction sites that I work at. My favorite are the tile boxes, 60 pcs per box of precut 12"x 12" cardboard spacers perfect size for my target needs.
I have used the Primos trigger stick (Tall) for three years, and like it very much. It takes some time to get used to the hold and balance but works well for my F/T needs.
LOL not a bullpup for sure! Even with the airforce lss setup it's still like pointing a javelin :D I have gotten used to shooting it from my trigger stick, but no go for real brushy Dence cover.
As a lefty I have had to adapt to a right-handed world. That said, I'm more comfortable shooting a rifle left-handed, with the cocking lever on the right side.
Welcome to AGN. The BRK pathfinder is a great choice. L.Leon's posts about the BRK rifles are well-known and respected. You can learn A-lot from his experience give them a read.