With 2nd runs, the amount the pomace is pressed directly affects the outcome. The more you press the first run, the less you leave for the 2nd.I have made '2nd wine' (red, from cab or barbera grapes) on 3-4 occasions. It has turned out rather 'thin' both in color and body/mouth feel, and most ppl didn't like it. About the only use I found for it is Sangria
I am thinking that given a good quality kit, + the used skins, would add some complexity to the final product. At this point, perhaps an exercise to be done in the fall.
The rule I use is for each 2 gallons of 1st run, add 1 gallon water + additives. Next time I'm going to do a 4:1 ratio. I'm also considering buying a couple of low end kits, reconstitute them, and add the pomace from 16 lugs of grapes.