tires that last the whole race will still lead to a lot of marbles. perhaps not as much as there is currently but you go to some of these narrow tracks (more so the city course/ones with barriers that reflect the marbles back onto the track surface) and you will run into the same problem as you do now...there is only one clean racing line so all anyone can really do is follow.
the other issue would be all these long straights followed by sharp corners...there is going to be hard breaking and thus a lot of flat spotted tires and when you combine the risk of a flat spot and an increased penalty of a tire stop (due to a race distance tire) you are only encouraging drivers to be less aggressive and that cannot be good for encouraging overtaking..
i dont think things have changed enough since 2005 to justify trying a race distance tire again.
