Even in my absence through most of the last Guild Wars 2 beta weekend event, I still lurked on plenty of community sites where I could. The two most prominent complaints I saw were about progression, namely weapon skill unlocking and major trait tiers. We’ve already covered weapon skill unlocks, and I think the most elegant change would be to change it to skill usage instead of critter death. It will be interesting to see the iteration that Jon Peters, ArenaNet dev, hints at. So, that leaves us with major trait tiers.
ArenaNet already put forth a pretty solid argument on why this current iteration is necessary.  What I find interesting is that now traits mirror skills a whole lot more. There are 5-basic skills, 3 more complex, more powerful utility skills, and 1 elite skill, and there are 6 basic traits, 4 mid-level traits, and 2 “elite” traits. Also at the top end only one elite skill or elite trait can be slotted.
Long ago in the days of Guild Wars 1, it was stated many times that Magic the Gathering was a guide to how the skill system was designed. They brought up the collectible aspect many times as well as the need to build a skill deck with only a few of many possibilities. While the Guild Wars 2 system is farther away in terms of build creation in that a large portion of the deck is built for the player with weapon skills, it is much closer in terms of rarity.