I'm very positive about my GT6 experiences so far. The game pretty much delivered on all the points I expected, but ofcourse that is a subjective assesment. The sound's are fine to me, and I get a pretty good impression of sitting in a race car with the options set to "large theater" and the ButtKicker turned up fairly high.
The best feature of GT6 to me is the new improved physics. There are a few bugs still to be ironed out (camber, slics in the wet and the pitstop bug), but still it is a massive improvement compared to GT5 (IMHO).
I would like to get most of the improvements you are talking about, but I don't understand why you are expecting them so soon? GT5 was released in 2010 with updates comming out in 2010, 2011, 2012 and 2013. Why would the updates for GT6 be any faster than that? They are still the same people doing them. I expect that we will get some of the updates this year, some next year and I would be surprised if nothing was planned for 2016 and onwards.
Three months in we have already got four updates with some bugfixes and some new stuff, so it seems to me that they are steadily working on the improvements. I joined a danish racing league and have gteat fun racing online every week. My biggest problem at the moment is getting kicked from servers from time to time. Maybe they are overloaded or there is some other glitch, but I guess that will be fixed at some point.
All in all I'm having a good time with GT6. We all have different preferences and I guess it's hard to please everyone. I don't care about livery or better sounds, because it won't improve my speed, but I understand why other might feel differently. What I don't understand is the impatience that many seem to have on these boards???
Pease and harmony to all of you.