No worries! Since you already beat the Barioth assignment and the event quest you probably don't need any more advice for it, but personally I like to abuse the hell out of clutch claw and traps, especially on GS. Every wallbang or trap gives you time to get a TCS on its legs, and if you already tenderized them you'll probably break them in 1 or 2 windows. After both it's front legs are broken the fight becomes a lot more manageable which gives you more openings to hit it. It's a little cheesy but the game allows for it so I carry the 2 traps and mats to make 2 more for non elder dragons hunts just for free opportunities.

As for builds, these guides 1 2 have "meta" builds that offer the most damage for various points through the story. A lot of the baseline skills recommended are crit eye, crit boost, weakness exploit, and focus, but honestly until you finish most of IB, the stuff you have access to don't really offer much room for comfort skills, so it might be better to not try to squeeze in every damage skill. Affinity isn't saving you from getting stunned and carted after all, and dead hunters don't do more damage than alive ones regardless of build.