100 Kts is way too fast in a Pitts even on long final. I use 100 mph (not knots) in the S-2A. In an S-1C this can be lower still. Touchdown is probably around 70 mph in the S-2A.
My mistake, based on me thinking in knots while talking with my Pitts owning friend who has been heard to say “I don’t ‘do’ knots”. Today I was doing some work with him and he said 105-110 mph on final and 100 mph over the fence for the S1-S, slower for the C he had before. Pretty much what you’ve said.
I soloed an S-2A with 68 hrs TT so you don’t need that much prior experience. (I did do my PPL on a tailwheel aircraft.) It does require determination and focus and a pilot who likes to fly by ‘feel’ instead of ‘numbers’. I’ve flown the S-2A/B/C and Extra 300L now but the best thing about the Pitts is that you get more feedback through the controls than the newer monoplanes. If you get the chance to fly an S-1 I wouldn’t hesitate.
68 hrs TT is pretty good for soloing a Pitts I did my Private in a tailwheel plane too. Part of me wishes I’d bought the S-1C mentioned above. It was a nice one, completely sorted out by my IA friend and his DAR hangar mate. Then it was sold to a guy who flew it home across the US. That guy somehow lost all the logs on the trip home. Then a couple of years later it was advertised for sale again minus logs, with price suitably reduced. $18K or 20K would’ve bought it and the logs could be largely recreated from computer records. I didn’t have hangar space for it and getting it back 2000 miles seemed like a big deal…
I flew an Extra 300 and came to the same conclusion. Great capability for some, but not my kind of thing.
I don’t think flying backseat in a Citabria will really help that much. Just go to Tutima in King City and Ben or Ken will sort you out in no time.
I don’t much enjoy flying the Citabria from the back (actually I don’t like the big mushy thing at all), so that’s good news 
Tutima is expensive but they have a good reputation. Another possibility is Budd Davisson and his S-2A, also fairly costly for dual in a $60K aircraft but what the heck, its probably worth it. 
Do you think it’s possible to run an IO-386 on mogas with 10-15% ethanol if the fuel lines can take it or are there any other problems?
The scope of the EAA effort to STC aircraft for auto fuel was pretty well publicized in the 80s, and it was a pretty big job. Alcohol was not a factor at that time and cannot now be used under the STCs. I think in principle you could build the engine to run on mogas if the compression is low enough, 7:1 or so like the Lycomings STC’d for auto fuel. The alcohol is a problem because the fuel scheduling needs to be richer, if first principles are to be followed. I’m sure that can be done too but it would take some development. I’d guess it would be a fairly large but doable project, and local regulations might affect your ability to experiment.
