Yemen, Syria, Facility tend to be my favorites. I would play Plunder or TDM if you want to try your luck with people camping.
Kal 7 + RoF and Para9 in case guy turns around.
Either Bargain or Monkey Man( Bargain to get Speedy G faster)
+Buy Ping or use the stat hat if you have it
Cloaked / Back In the Saddle (lvl 2) / Disruption
I was in LU and just hung out around the 'climb' points to the second level on LU. don't bother with ping; it makes you look cheap.
I wouldn't mind kill farmers on my team in plunder. They're still doing something for the team. When I needed 50 Plunder wins I got teammates who would team kill and carry the treasure to the opposing team's base.
Don't worry too much about being a "kill farmer" in objective games.