You could use any system to keep a mother, but in general people don't use set ups known for fast growth. Mothers are usually kept more simple. And yes a DWC would be great to keep one or several mothers. I keep mine in soil and under fluorescent lights because I don't need them growing real fast and I don't want to put any work into them. I just water them occasionally with my nutrient solution when I mix it for my hydro plants.

Hydro does not have to be complicated. I am very certain it is overall much easier for me to achieve good results in hydro. Just look at the Emily's Garden. Plants will grow much faster in that than in dirt, and it's so simple even a cave man could do it. It's probably more simple than growing in dirt.

I highly recommend hydroton and not rockwool. Rockwool is not for beginners.