FOSS gamedev and creative worlds

I would like the ocean to be deeper and more realistic, deep ocean is known for its mystery. Are there map generator that could generate realistic ocean. I would prefer to it to look like this.

The existing mapgens can do this if you use custom noise parameters.
Mgv5 has the deepest oceans by default.

I personally believe that a map with 2-3 huge, realistic oceans, 20 or so GOOD rivers, and countable, mappable numbers of huge, beautiful biomes with tall mountains, deep valleys and vast, flat plains is much better than hundreds of "ocean-minilakes" + pee-ponds + sausage-channels and annoying hills and dips. I wonder if the devs have ever taken a look at a custom-generated worldmap - it looks like a warzone! Also, this isn't a rant, as I know there are ways to easily improve this.
Also, I've heard about the parameters and am very interested. Can you tell the params to modify in minestest.conf to change it like this?