Can anybody give me 3 cool japanese names for these meanings?

I want to say that I prefer you guys to make to up the names instead of giving me a baby dictionary because i already tried that a thousand times.Also all the names need to be for males.

First is: Strong, confident song

Second is: Cool, lazy man

Third is: Playful melody

Also for the third name, if you want, you can give him a nickname with the name if he was a singer or idol, I would appreciate it.Can anybody give me 3 cool japanese names for these meanings?
First: Kei (means strong)

Second: Ryou (Means cool rain)

Third: Nijiro (rainbow coloured. To me, A rainbow resembles a song and the colours make it playful)

The nick name would be niji.