I actually like the way they did the half races. I know that many complain about it, but I can see how trying to come up with an entry for each possible combination would be difficult, not to mention hard to maintain going forward as new races are introduced. And letting players pick and choose from each would be a min/maxing nightmare.
I like, at least so far, how they have introduced levels to feats as a way to bring them under control and enforce some measure of balance on them. In the past couple of Editions, feats were always out the center of min/maxing horrors, which is why they were more restrained and optional in 5e.
I like the division of spell lists into the main three, and see it as long overdue. Of course, there is a lot to still see here.
I like that monsters do not crit, as it simplifies them more and makes CR estimates somewhat easier. It goes further down the 4e road of Monsters & NPCs having different mechanics from PCs, more suited to their purpose in the game. I do hope they give more monsters "rechargeable" abilities though.
I like the background focus, as I see "race" becoming more and more of a hot-button issue (both in and out of game) that they would want to shift more of the heavy lifting to backgrounds. I foresee a time when race is largely a cosmetic option that is selected.