Wow, you recommended so much, and to think out of all the Manhwa's you mentioned here I only red The BreakerAlso try Red Storm - Super strong master makes super strong student.
The Breaker ( His master is seriously OP, but he gets pretty strong too.)
Special Martial Arts Extreme Hell Private High School - MC has some wacky OP super powers when he uses them.
The Scholar's Reincarnation - Over powered MC is reincarnated as a child with the same amount of power.
Ultimate Legend: Kang Hae Hyo - MC has amnesia and doesn't remember he used to be mega powerful.
Most of these are Manhwa if you don't mind them Many are really worth the read!