Infinity slayer: 
DMR, Boltshot, Always 
One jetpack with shielding and dexterity frags 
One prom vision with ammo and shielding frags 
One jetpack with ordnance and shielding frags 
Best tac packages are shielding and resupply for infinity slayer, since mobility isn't necessary unless you're on btb and mobility makes people want to sprint more than they should 
  
Btb 
Light rifle plasma pistol plasma nades ammo mobility jetpack, may switch to one of the dmr loadouts above depending on map size 
  
Objective  
Br Boltshot shielding regen ammo, ammo is crucial because no personal ordnance on objective so map ordnance is more important 
  
Pretty much always dmr Boltshot for smaller maps, dmr magnum for bigger ones since Boltshot is useless at range and magnum is underrated 
Should always have a shielding loadout, an ammo loadout, and a dexterity loadout. Shielding and dexterity for general slaying, ammo for ordnance rushes/personal ordnance drops. I like to have an ordnance priority loadout for slayer since its fun to mix things up 
  
Mobility is crucial on btb but don't let it control you; people with mobility tend to want to constantly sprint but if you're always sprinting you'll never get first shot and you'll die way more. 
  
I generally like frags because they're harder to dodge 
  
Jetpack is probably top 2 best armor abilities, thrust is ok for some maps like solace where you can fly across map with the lifts but should always get a couple jetpack loadouts and a prom vision(wetwork sucks and almost nobody would pick stealth over dexterity or ammo and even if they did they still show up on vision)