Kaz states that the GT series is first and foremost a driving simulator, basically the racing aspect (fun bit) comes 2nd or possibly 3rd after photo mode. This is shown by the poor choice of offline races in GT5 and the dull and unadventurous AI. This needs to change in GT6, I have a feeling it won't.
A lot of aspects of racing are missing, challenging AI, offline custom races, qualifying, fastest lap, offline grid starts etc.
But if it is a driving sim then why are the gear changes modelled so poorly, just watching vids of GT6 you can see the gear changes are exactly the same as GT5 no effect to the car other than less revs on the counter, a gear change in a car is part of the thrill, it's where you get the kicks of power, there is no drama shown in GT. GT5's changes are all sequential shifts no matter what you're driving but without any noticeable effect on performance. Plus what makes it worse is that you can quickly shift from 6th to 1st at 300km/h without a hiccup.
The engine sound is so pathetic in GT5, one of the worst has got to be the BMW M3 it's diabolical, it sounds like you're driving a go kart. So many things going on which make the driving experience feel less desperately need to be addressed in GT6.
Sadly this seems to me to be Kaz's version of COD, just keep churning out the same old, same old because the masses will buy it. No need to change the focus or consider what makes other driving sims so popular because GT rules. It did, but for me its hat started slipping back in GT4, looking prettier but getting duller and more wooden with each version.
I bought a PS3 solely for GT5, even though I have a large library of games for it GT5 is the only thing i'll play on the PS3. Sadly my PS3 is gathering dust as I get more kicks out of Forza 4 and rFactor. Everytime I try GT5 it doesn't fail to disappoint and I have to immediately resort to the personal faves.
Please Kaz amongst many of my wishes make an entertaining sim that's not purely focused on the online world.