Feats / Feat chains for a natural attack build

[Gallant Armor]

I have looking for some feat ideas for my Gestalt (Vanguard) Slayer // (Internal Alchemist/Vivisectionist) Alchemist dex based natural attack build.

We are currently at level 8. I am not sure how high the campaign will go, but I like to have options available up to 20 and currently my plan has 4 feat slots that are empty and a 5th I could see replacing.

GM is open to 3rd party on a case by case basis.

[Backpack]

hammer the gap gets good at higher levels, but otherwise im not sure as far as most feats go. Pfs wise, the way i play most often, you kind of get to just take whatever sounds fun. If you really forced my hand id consider taking, skill focus survival->eldritch heritage(orc bloodline) touch of rage which is a very iffy moment of greatness like buff-> Imp eldritch heritage, Fearless, which gives you fear immune and +2 nat armor. Or for more offensive take strength of the beast giving you +2 Str at lv11, +4 at 15, and +6 at 19. Note that with dex the defensive option is 100% better. But i'm more experienced with the Str builds, mayhaps someone will be able to help more then i could.

[Gallant Armor]

Hammer the Gap is a good idea for extra damage.

I dumped Cha to 5 with racial mod so eldrich heritage is a no go sadly, if not for that I would definitely consider that.