Hmm, not sure about the rating. "Offline" B-Spec had its use once, to earn some cash with little intervention, in the times before remote racing and extremely well paying seasonals, but it has kind of lost that. B-Spec was still good for getting to level 40 easier, so you could buy all the X2010 back when these were good trading currency. But it's lost that too. Now the only thing "offline" B-Spec is good for is for quickly leveling up new drivers to be used in remote racing. As for remote B-Spec, I actually quite like it a bit, it's nice to sit down and watch some races where you actually compete against others, and can cheer for your Bob to win. For me it's remote which saves the whole B-Spec feature.
Integration of B-Spec into A-Spec would be great in my opinion as it was in GT4. So useful for long endurance racing.
Now that would be a feature! If you really want to bring any kind of "real" aspect to the 24-hour endurance races, skip the pause button, forget about the save feature, don't ask anyone to do it all in one sitting (I still don't get how anyone could argue for that being the most "real" option), just let us pick a few B-Spec drivers to race with. For Le Mans, given it's 3 drivers, you'd do 2 4-hour stints, with 8 hours in between, and for Nuerburgring, you'd do 2 3-hour stints with 9 hours in between. You could time the race to do your first stint just before bed, and then you'd have 8 or 9 hours to sleep, have breakfast and get ready for your next stint. And if you're not there on time, well, then you fall back and have to make up time. To me, that would be the most "real" option, and I think it could actually be quite fun. But then again, is that going a little off-topic now?