I just thought of a possible time save, if only you have the patience to do it.

During gameplay, you level up naturally. But once you reach the max level, it's pointless to level.

However, even when you go past max level, I'm fairly certain you still gain a minuscule bonus of like 1% to certain gameplay mechanics, ie swing speed, melee damage, etc.

So, if there isn't a true cap to how high your "Superior Level" gets, you could complete a ton of runs, getting an insane max level, then the following NG+ run could have you playing at insane speeds and doing a ton of damage where you could one hit every enemy.

Would this be a possible technique or not?

Once you hit lv 30 in this game thats the cap on everything.