The classic 30 is a very, very underrated amp. I can get any tone I want out of it. I've ended up with electroharmonix/JJ tubes and a g12h/greenback combo and it sounds amazing. First chaning to JJ tubes really warmed up the amp and got rid the harshness, and putting the EH in v1 later really added the sparkle it was missing. This speaker combo is also amazing. My favorite setting is about at 7 and it's perfect/ clean when you play soft and breaks up nicely when you use some attack. Very touch sensitive.
Also, for my overdrive I use 2 tubescreamers. (one stock and one modded by Spina) I love the sound of these things but a lot of people don't. I've also tried a Plexitone and it got along with my amp pretty good but it just wasn't my taste. (not a humbucker/hard rock tone fan much anymore) These are the only two I've tried but it's been very pedal friendly so far.
Another thing is, most people complain that the OD channel is too harsh. It really is. But, I really like the sound of my post gain cranked and using the pre gain as volume. It still gets a little harsh as I turn up the pre gain. I VERY seldom use this channel. I think peavey should make a lower watt version of this amp/ get rid of the OD channel and boost switch (that thing sucks) and it would be a perfect amp.