Ground Zero

Ground Zero is most likely the least played map in Tarkov. Do not go there, its bad, it is literally just a map you have to do quests in.

Streets of Tarkov

Streets has pretty good loot spots and one of the best marked keys in the game. Although the key is impossibly rare.

Interchange

If you run Interchange you want to kill people, it is also great for building material loot.

Customs

The best loot on customs is either Reshalas base or Dorms. Library is also quite good.
Also great place to safely run stashes.

Factory

Factory is for killing people, nothing else to be honest. Maybe okay loot in Office but thats it. Beware of Tagilla.

Reserve

Dome. Dome is the best loot spot in Tarkov, no enemies spawn there and you have tons of varying loot.
It also leads to the underground bunker, that has a marked key door.

Woods

USEC checkpoint, USEC Camp, Emercom and Plane are the best to loot, good valueables and medicine items.

Shoreline

Resort and Scav Base are good loot spots aswell as good spots to kill in.

Lighthouse

Avoid water treatment plant. It's the Rogue base, they are very good, and the loot isnt.

Labs

Labs is a high-risk high-reward location. PMCs and Raiders spawn there. the best loot spawns in Labs.

Terminal

The newest map in tarkov, it infact is a map that exists (no info on it yet.).