Crit and versatility sim mostly the same in most cases, it really depends on your Deadshot traits. Crit gains more value when cleaving, which is mostly when you want to be playing Outlaw, so I always prioritise Crit over Versatility.
Haste: increases your attack speed and energy regeneration.
Critical Strike: makes your abilities do double damage.
Mastery: makes your main hand attacks proc an off-hand strike that does damage as well as activating Combat Potency.
Versatility: increases the damage that you deal, and decreases damage taken.
In most cases you want to be stacking Crit since it's way better for M+, with versatility being a close second. Haste isn’t as great as it used to be due to energy capping which makes it drop in value.
The best way to calculate stat priorities for your character is to "sim" your characterFind out how to sim
Dwarf > Blood Elf > Undead (ST only)
Off-Hand - Versatile Navigation
Rings: Accord of Critical Strike