If i where you dont spend your robux yet. Spend your yen in ro ghoul for touka and farm until you reach level 750 si that u can easily grind level until to 1000. Spend your robux when you reach level 900 so that you won't grind rc and buy a Lycan or Eto(i recommend takizawa cause eto and lycan last stage must be at level 1500 unlike takizawa). But i recommend more if you use robux in ccg because its more easy to grind yen in ghoul because the prices of kagune is more lower than ccg but in ccg is more boring but inexchange of your patience you can enjoy ccg.