I didn't vote for Obama either time. I voted for McCain and then none of the above. I really wasn't a big fan of Obama's, although I don't think he was bad at administering our nation with a few really significant exceptions.
The biggest one for me is that, while the Iraq war was a mistake in retrospect, when Obama took office things had really turned around. There were the right kinds of relationships between the U.S. Military and various local leaders in Iraq. Things were finally starting to go right. Then Obama pulled out and left the void that ISIS eventually filled. Absolutely enormous blunder on his part. Not only did he essentially throw away the lives that were lost getting us that far but he cost many many more lives by giving ISIS such a golden opportunity to grow in a place we previously had control of.
The next one OB mentioned. Obama deported A LOT of people. The stories that really stuck with me were the people who were deported for very minor crimes after having served in the U.S. military as a path to U.S. citizenship. I served with many people who were there so that they could become citizens. I imagined those people, my friends, losing that dream after doing more for the U.S. than the majority of U.S. citizens because of moving violations or other relatively minor crimes. Really disgusting.
So I've shared my criticisms of a Democrat President, and they aren't things like "I didn't like the language he used," "I didn't like his crooked smile." I gave real meat there.
Let's hear you criticise Trump. Not for his style, let's here you complain about some substance.