Advanced Quarry + Studied + Sneaks > Weapon Training + Gloves, especially if you already have another Fighter. Mut's basically +2 AB but hurts Will Saves (already a weakness) and Perception checks.
Improved quarry gives +4 insight on attack rolls.
Mutagen gives +2 to AB (or +2 dmg), but then you have weapon training +2, and greater weapon focus another +1.
Also, you get access to weapon specialization that gives +2 dmg, and the gloves as you said that increase weapon training.
Quarry has no mythic upgrade, while weapon focus and weapon specialization do.
If you get both you get another +2 AB and potentially +5 dmg at Mythic 10.
You leave on the table 3d6 sneak attacks and +2 AB/DMG from studied target and the advanced rogue talents that are not that great for ranged anyway.