Material: Buttressed/BoS/Polished (highest resistances),
Arms: Deep Pocketed (more capacity) / Stabilized (scope).
Legs: Deep Pocketed / Sleek (faster movement speed on crouch).
Blocker: No target should be able to come close to you. However, if you have problems with this, this card will be perfect for such situations.
Radicool: Only for low HP builds. This card gives you up to 5 Strength which means that you will be able to carry more stuff with you.
Lifegiver: More HP you have, more hits you can take. Simple as that.
Rejuvenated: Increases benefits from being Well Fed and/or Well Hydrated. Your thirst/hunger bar should be above 75% to make benefits from this perk card.
Tenderizer: After first attack your target will receive 5%/6%/7% more damage (depends on card level). You can use only first rank of this card, because that additional 2% is not really worth it.
Demolition Expert: This perk is useful for players who use explosive weapons. It will increase damage from explosion, not base damage of the weapon.
Nerd rage: Must-have for low HP builds. Remember that you have to be below 20% HP to make this perk card works.
Dodgy: Currently during PvP encounters you can't use V.A.T.S. (on most weapons), so Dodgy is one of the most important defensive perk. Every shot you receive will be reduced by 30% in cost of 30 Action Points.
Long shot: More range means higher damage on long distance. Must-have for PvP. You will want to change that with Concentrated Fire.
Adamantium skeleton: Prevents your limb to be crippled and reduce stagger effect.
Fireproof: Must-have versus explosive weapons. If you don't want to use this card you can use Dense mod onchest piece of armor. You should know that this perk card reduces damage from flame attacks (ex. Robots/Laser Rifles).
Adrenaline: Increased damage up to 60% (at max rank) for 30 seconds. If you kill target before the effect expires duration will be refreshed.
Gun Fu: In V.A.T.S after kill you will deal 10% more damage to next target. In most cases 1st level of this perk is optimal.
Mister sandman: At night your silenced weapons (with silencer) will deal an additional +25% damage in sneak. Remember that day/night system depends on time in your Pipboy.
Secret agent: Only for stealth boy users. It will increase duration by 100%.
Serendipity: One of the most important defensive perk for low HP build users. At maximum rank you will get 45% chance to avoid damage while your health is below 30%.
Escape artist: Remember that running is not same thing as sprinting. It is highly recommended for sneak builds to keep unnoticed.
Sneak: If you don't have problems with detection you can skip this perk. It is mostly for players who have problems to be unnoticed.
Chem fiend: Do you want to keep your Berry Mentants as long as possible? Use this perk to increase duration of your chems by 100%.
Curator: Useful perk for players who use bobbleheads and magazines. Curator will double duration of this two things.
Better criticals: Useful perk for high HP builds, in case of low HP and tanky-anyway builds, can also be used instead of Serendipity. Your criticals in V.A.T.S. deal up to 40% more damage.