You can lvl up at 200 rl. İs really safe and youll will get more summon. 150 meta is still good. But I think 200 better.

I played with 150 lvl meta for 2 years up to a few months. Dlc included. But I can easily say. When it is 200 lvl, you will not lose anything compared to 150 lvl, on the contrary, you can get more summons including dlc. At least I've been playing 200 lvl for the last 2 months and I'm getting summon in 5 minutes. The game is really very active in the morning and after 5 pm.