I'm pretty sure this is what I want to do on my S2R but I was hoping to get some feedback from other people riding the same setup.

It's not uncommon for folks to mix n match from the same manufacturer with putting a softer tire up front and harder in back. Sport and sport tour combo. AFAIK as long as you stick to the same manufacturer and one step away in the product family i.e. Race->Super Sport->Street Sport->Sport tour->Tour->Big Fatty Cruiser you should be fine.

Does anyone know if the middle of the 2CT PP is the same stickiness as the plan PP tires?

You can run PP 2ct almost up to the intermediate group at track days. I would not worry about the stickiness for street use.

It's a pretty popular combination for people that use their bike for both commuting and more spirited riding.

I recently (500 miles) put a PP 2ct front / Pilot Road 2 rear combo on my 1100s. I switched away from Bridgestones (f BT016/ r BT023). Feels REALLY good so far. I like the combo and would be considered a "spirited" rider. I have put 14.5k miles on my bike in 16 months and work from home so no commuting but really wear rear tires. I get about 3K out of an 016 and 5k out of an 023. Hoping for at least that out of the PR2.

I just ordered a regular PP and a PR2. I'll give you my review once they are on and ride a couple K.

I'm running a Pilot Power in the front and a Pilot Road 2 in the rear.  Only because the last front lasted 5k longer than the last rear, which lasted to almost 10K. (awesome) So I thought I would try a PP for the next 5k till both tires need a replacement.  The different carcase shape changes the way the bike turns.  Seems a little gentler turn in.  In a good way.  Others have described my bike as a little "divey in the corners" So I think I need to adjust the steering geometry. 

I have never run out of grip even on the pilot roads so I can't give much experience there, but I'm really digging the way the bike turns in now.