There's no question that set design has, for the most part, improved over the year. Likewise, parts and color selection have grown equally, providing us with more possibilities now than ever.
My only real gripe is how the quality of the bricks themselves has suffered since Lego exported production to Mexico and then China. Both dimensional consistency and color matching have been a little slack lately. Personally, I have some Lego that has less grip than some of my old Mega-Bloks, and some identical parts that grip a lot harder than Lego should. My friend Jason (Doctor Mobius
on flickr) built a giant spider coated in hundreds (possibly thousands) of levers
he got off the Pick-a-brick wall. Every time the spider was moved to a new display area in his house, or to a convention or public display, countless "hairs" would fall off. I usually got roped in to putting them all back on, with a tub full of extra levers, because some would inevitably get lost. Some of those lever bases literally would not grip a stud, and would fall off if turned upside down. Others simply would not fit onto a stud without cracking, and then having the same problem as lever bases that were too loose.
A few months back, I was helping another friend of mine sort a bunch of Lego he'd bought in bulk lots (can't remember if it was Pick-a-brick wall or stuff he got from our LUGbulk order), and as we were stacking 4x8 dark bley plates in groups of twenty, with overhang on the ends to make them easier to separate later, we noticed that each stack was not precisely the same height. We compared, and found that in a stack only 20 plates high, the difference between the tallest and shortest stacks was over a plate and a half. That may not seem like much, but imagine you built a micropolis skyscraper using some of these plates as the base? Your whole tower would be leaning!
Speaking of leaning, the early waves of collectible figs coming out of China? Some of them had one leg longer than the other! They actually could not stand unless connected to their base!
Color-wise, there have been numerous comparisons out there showing the differences one encounters over the lifetime of a color's production run. However, I've started noticing color variation within the same set, or within the same bucket at the Pick-a-brick wall. Anybody get some of those pink 1x2 slopes one the wall within the last two years? There were four shades of pink in that bin, all "close enough" within Lego's recent lapse in quality control. I have a 1x4 brick that is supposed to be dark bley, but is almost exactly halfway between light and dark bleys. And don't even get me started on all the trouble Lego has had keeping reddish-brown and dark red even close to consistent. Seriously, check out this section
of the Hill Valley Clock Tower from Back to the Future that a member of PortLUG built, and see all the color variances of dark red and reddish brown. This is probably the only case in which I've ever seen the color variations being used as an advantage, and it showed when the finished product displayed
at the most recent show we did at Guardian Games (note the presence of my mini-fig scaled Clap Traps on the front steps).
All in all, Lego may have increased their color pallet and parts variety, but they have made up for it in poorer quality control. We're fast approaching Fifty Shades of Bley.