Wolfe,
Yeah, i am at sloclone´s...I took a look at Jed´s OD3 switching but i didnt really understand how it worked. I had some talks with Joey about using CMOS or Fets for this, but i still dont understand how the signalling works to ´tell´ whatever is switching to do its job. There´s also that guy who cloned a 3 channel DR and the switching is on the schematic
If you want a SS loop you can just get TUT´s loop. I have it somewhere on my email. You really dont need much more things to do a parallel/series loop, as any serial loop can turn into a parallel one with just a couple mods. If you really want to go just serial, just use the 5150 loop, or take a look at the forum and it has a few SIMPLE but transparent loops.
As for the mid sweep thing, did you take a look at the Krank Rev thread that was going on a while ago ? IIRC, its is just a 250k pot going from the cathode follower, so it could go from 0 to 250k slope. I had done this to one of my clones before but it was a 33k resistor in series with a 50k pot. So, it could go basically from marshall to fender slope. IMO it is really not worth, and it is easier to put an ON-OFF-ON dpdt switch, and a 33k resistor and whatever values you want on the switch. This way, you could have, for example, 33k (marshall), 47k (SLO/DR) and 100k (Fender) slope resistor. Or you could just use a push/pull mid pot that could change the slope resistor (or the treble cap). IMHO it would give a cleaner external layout.