I tend to agree with the OP on most points that he makes.
-Graphics/Textures- I am astounded at the beauty that Rockstar managed to muster out of current generation consoles, the game at many points has left me in awe of how beautiful and realistic it is.
The water is something that I always find myself marveling at every time I play, only to be rivaled by the cities night lights from the air.
-World Design- I really feel as though some areas are amazing while some seem sloppy and not very thought out. The Beach is a great area with a perfect transition of 3 different environments, the transition from city to beach to ocean is very well done and spaced perfectly.
The city has some really interesting areas but far to many areas that are just flat out boring and lack the ambiance of the rest of the area.
The countryside I feel lacks that special something that gives me the urge to return to, I always feel like I just want to bypass it completely by flying to my destination as opposed to driving through it.
The only real strong point I feel is the fact that they gave us some huge mountainous areas that make for some great fun with a vehicle.
-Missions- I am split on, while i enjoyed most I feel as though they lacked that epic sense that we have gotten from some of the former missions of past GTA titles.
I cannot recall any real memorable moment that I thought "wow, that was amazing".
They just seemed rather bland and I feel as though they were overly easy to accomplish, I only recall actually having to reattempt a mission once or twice in my whole campaign.
-Driving- This is another spot that I feel kind of split on, although i have had some epic close calls and amazing high speed driving sessions, I feel that they lack that sense of accomplishment due to the fact that handling and driving in general is very easy.
So to sum up my feelings, I think the game is far to massive to be evaluated as a whole, there are some really strong points and some rather weak ones.