Start by looking at the hull bonuses for your ship. Brutix can be fit for blasters (short range brawling) or rail guns (long range kiting) and has bonuses for active armor repair.
You can’t fit large turrets on the Brutix - nor would you want to. Larger guns have problems tracking small targets. If you’re mostly fighting small and medium ships, medium turrets are the way to go.
The skills that influence hybrid turrets are described at: https://wiki.eveuniversity.org/Turrets#Gunnery_Skills