You've already seen a lot of the main things I'd recommmend, but there are a few good recommendations I can still give.
Code Geass (Action/Mindgames/Politics - SUPER good, and I'm sure you've at least heard the name before. Definitely check this out.)
The Melancholy of Haruhi Suzumiya (Slice of life/Character relations - Not sure if this would be your thing or not, but it's definitely one of my favorite series, taking a place in my top 5. The plot comes and goes, but the series was just so enjoyable for me and it always left me wanting more. If you do want to watch it, I'd definitely recommend watching it in chronological order rather than release order, so you can feel free to pm me or whatever if you want help with that. The timeline can get kinda tricky to figure out.)
Charlotte (Supernatural/Character Relations - I saw that Angel Beats! was on your top ten, and this instantly stuck out as a series missing from your list. Charlotte is another anime by the writer of Angel Beats!, and there are actually quite a few Angel Beats! references distributed throughout it. The ending is kind of rushed and the plot comes out of nowhere in the middle of the series, but it was realllllly good, and I feel like it should be inn my top 5, but there just isn't enough spaces. Definitely check it out if you liked Angel Beats!)
To Aru Majutsu no Index. (Action/Supernatural - This is another of my favorites, though not everyone enjoys it the same way. I'd still definitely recommend this, and if you like it, be sure to check out the sequel series and the Railgun spinoffs.)
Sword Art Online (Action/Virtual Reality - There are people who will hate me for recommending this, but I have to do it anyway. Yes, it's overhyped, no it's not a perfect series, but it's still very enjoyable and takes the top place on my list despite its flaws. If you enjoyed Overlord and .hack, this should be right up your alley.)
Log Horizon (Virtual Reality/World Exploration - I always see this series as SAO's counterpart. While SAO focuses a lot on the action and fighting, Log Horizon spends more time exploring the world. That's not to say there isn't plenty of fighting as well though. Again, if you enjoy virtual reality MMO anime, check this one out too.)
Accel World (Action/Virtual Reality - Another anime written by Reki Kawahara, the creator of SAO. It's a different sort of virtual reality than most anime, almost leaning more towards augmented reality. I enjoyed this series a lot more than I expected to, and I'm eagerly awaiting the recently announced season 2.)
Maoyuu Maou Yuusha (Fantasy/Politics - I've only found one other person on Reborn who knows of this series, being Acqui, and she only knows it through the manga. Regardless, both of us love it to death, though I have a somewhat hard time recommending it. I feel like the anime will bore most people to death, and in general, I don't think most people will find it very good. Despite that, it has niche fans, such as myself, and as another of my top 5 anime, I feel obliged to recommend it anyway.)
Hopefully you can find something in there to watch! Feel free to pm me with questions or whatever. ^^