I didn't know that spotting for artillery got you many points. How many does it get you?
It does not, you get the targetting assist score only when artillery will use your spot and kill the enemy within it. It gives you 2 points per kill.
Tank Kill - 7
Defend Flag - 2
Kill - 2
Spotter - 1 assist point for Teamwork
As TS said, tank kill score depends on how heavy the enemy tank is, and how heavy your tank/weapons is. Inf vs heavy armour scores the most, but heavy vs heavy tank isn't that much of a success. AA gun kills are pretty valuable too IIRC. I think there are 4 points for destroying an objective. Also, you get 5 points for killing a Squad Leader.
Neutralizing the flag gives you 2 points and capturing it another 3, that is 5 in total for capturing the flag when you do it alone (or be first in the flag zone). Assist score for neutralizing is 1 and 2 for capturing assist, I think?
Kill assist while infantry is also 1 point, you get it when you only wound the enemy who is later killed by someone else (while still wounded). You don't get the score if the enemy will patch himself up back to full health.
Also, a thing worth a note: when you're in a dogfight and the enemy will bail the plane like an utter shit he is only to prevent you from getting your well deserved kill, destroying the empty plane right after he bails, will still give you the score. Bailing is of course acceptable and fair only when pilot has his parachute with him and is planning to use it, instead of just killing himself by hitting the ground with full speed.