I'll recommend one of my favorites:
Jyu-oh-sei: Planet of the Beast King
A surprisingly solid sci-fi series ( try saying that ten times fast ). The story begins in the far future where humans have migrated to other systems and whatnot. Two young twin brothers, Thor and Rai, return home to find their parents murdered. Almost immediately, the two are abducted, and find themselves stranded on the planet Chimera- an incredibly harsh, hostile planet used for capital punishment.
As you can see, the series wastes no time in getting going- with only 11 episodes, it doesn't have the time to. However, this series does more in 11 episodes than many series do in 20. It does suffer a bit from its short length, but in spite of this handicap the plot is very solid and satisfying all throughout, the production values are great, and if you've got 11 episodes-worth of time to kill, I recommend spending it on this series.
+ - intriguing plot and setting, populated with interesting characters
+ - great animation and sound ; good voice acting in both languages
+ - doesn't require a major time investment
- - the short length leads to a couple of plot holes that you could drive a mack truck through
- - the short length also renders some characters superfluous ( I kid you not, there are at least two characters who are in the opening credits who get roughly 5 minutes of screen time before being discarded )
Personally, I give it a 4.5 / 5.

The series can be watched in both English and Japanese on Funimation's website for free.
- myFork