I finally reached lv50 about a week ago and I have about 560k SED at the moment. However, I would like to lean as many new things to try in the game as I can. Everyone's Feedback is greatly appreciated.

Once you got a lot of N cards at +5 ex level, stack N wild cards if you have remaining N gacha tickets or in the opposite way, farm pero in GHQ (300-700 per N-R card, Chance time has a higher rate than bonus stage). You should have more than 300 stamina at this level

Repeat process once you reach 1M SED (Ex level +10)

True. Thanks for the tip man.