As i started to rank up my class i noticed that im getting like 3-8 class points per kill in battlegrounde. Is it some kind of nerf for map or have they reduced overall class points gains?
You need to kill higher level monsters, try battlegroundf
better go in /join bloodmoon kill those "darkness" monsters i think? and use the bot grimoire so that you can use the infinite attack range
Darkness monsters, nightmare or nothing are all good CP points sources.
Use boosters and bot if you really desire the need.
Also note, the monsters in battlegrounde vary in level from level 65 to level 85. If you're level 85 and farming the level 65 monsters for CP, you'll get very little CP. If you farm the level 85 monsters you'll get a lot more.