Ken,
I think you are right... Being region 2 or 3 does NOT guarantee better picture. I own a number of regions 2 & 3 discs (korean, chinese, japan, hong kong, and british), and the quality varies. Some are excellent (much better than the region 1 counterpart), and some are not. I found region 2 & 3 discs often have softer picture and saturated color even with better clarity. A lot of them have DTS tracks when its region 1 counterparts don't. I bought some region 2/3 discs just to have DTS track, and I think the DTS tracks on korean and japanese disc are very well done.
One thing to be carefull about though... Sometimes, hong kong dvds look legitimate and plays great, but they are not. They are copied dvds, but they have all the color artwork and the discs are mass produced with title directly printed on the disc. It is almost impossible to tell. Well, these discs are cheap (I mean, really cheap), but they often have playback problems (freezing, skipping, audio breakup, etc.). So beware...