From your experience which scenario in the graph below would you say best describes the performance of the three most usual tyre "genres" (purely track-oriented, dual purpose, and purely road oriented). I'm a bit at a loss and tyres are too expensive for me to make light-hearted experiments. The "x" axis is actually a temperature axis but instead of giving actual temperatures, I used types of riding because that's what determines tyre temperatures in the real world and ultimately that's what is important to me as I mostly do canyoning instead of track days. Both scenarios are strictly for dry riding.
Probably closer to scenario 2, although it also depends on ambient temps, as well as tire temps. Race tires have zero grip when they're cold, even if it's 40°C out. If you use tire warmers, they still have phenomenal dry grip even if the track is freezing cold. Road tires have a very flat grip curve regardless of temperature, but max grip will be lower as you've already figured out. If you plan to never ride on the track in the rain, a "hypersport" tire is probably the way to go - S21, M7RR etc. They're nearly sticky enough for an expert race pace, but they'll still get you home if you get caught out in the rain.
I totally agree with you on not going with race wets. But I think Pirelli Rosso III is also a good alternative. I did 3 track days with Pilot Road 4s in Greece last year.
The Road 4's are nothing like the new 5's. I've heard the same feedback as you and I don't intend on taking the 4's on my VFR to the track. I spoke with a Michelin rep just last week, and he says the Road 5 has more dry grip than a Pilot Power 2CT. That blew my mind. A decade ago, the 2CT was my go-to track day tire. I probably did 30 track days on 3 sets of them, eventually riding them in the advanced group. To think I could do the same on rubber that has better wet grip than a Road 4 shows just how far tire technology has come in so little time.
I've just about finished off the Rosso II's on my R3. I mostly commuted with them, but I also did 2 track days and they're a true do-it-all tire. Granted we're only talking about 35 horsepower, but my lap times were limited by ground clearance and not by the tires. I have a brand new set of Rosso III's that I'll mount in the next couple weeks, and I'm expecting more of the same. They get my vote for your needs.