My planned courseload for next year is the following:
AP Statistics
AP Government
AP Economics
AP World History
AP Physics C
AP English lit
I will also have a study hall period.
I want to take all these classes, but I’m also a little worried that I might be setting myself up for a miserable senior year.
That’s a really challenging courseload, but I think you’ll be okay. Colleges will like to see that you continued to challenge yourself senior year, where a lot of other students start to slack off. Plus, if you pass all the exams, that’s a lot of college credit! The classes are a good variety of subjects and not all of them are super hard and mega-workload classes. As long as you’re willing to put in the time and effort, you should be fine. 
Here’s what I know about the courses you’ve chosen:
AP Stats: Haven’t taken this class and it isn’t offered at my school so I don’t know much about it, but from what I’ve read on here as long as you’re fairly decent at math and can read graphs/charts pretty well, it will be easy and the courseload isn’t too awful.
AP Government: Most of my friends took this class and said it was one of the easiest they’ve ever taken. All of them passed the exam with a 4 or 5. It isn’t much work and the material is easy to comprehend. I don’t think you’ll have any problems here.
AP Econ: I’m currently taking AP Microeconomics and took AP Macroeconomics last semester and I loved both of them! They’re pretty straightforward and mostly based on concepts and easy to learn graphs. As long as you know your vocab and decipher a graph, it’s a breeze.
AP World History: I heard this class has a pretty heavy workload, but I don’t think the material is too difficult. My school isn’t offering this until next year so I’m not sure. I’d look around on here to find more about it.
AP Physics: I’m in Honors Physics right now and it’s pretty interesting! However, I’ve heard the AP Physics classes are pretty difficult. It will probably be the most difficult out of the 6 you’re taking, but I think you’ll be able to manage if you’re a math/science person, can set aside time to study, and have someone to go to for help (even if it’s just the teacher).
AP Lit: I’m taking this class right now and it’s great! It’s a lot of reading and a little bit of writing, but I don’t really have to put too much effort outside of class into it and it’s not difficult at all. If you enjoy reading and can write decently, you’re all set.
I hope this helps a little bit, and feel free to ask any more questions (especially Econ and Lit!)
Good luck.
I think you would do just fine in those classes. Some may be a challenge but it’s good to challenge yourself. I’ve heard AP Stats, AP Gov., AP Econ, and AP English Lit have their challenges, but for the most part are fairly simple courses. I agree with the person above that Physics will probably be the toughest of the six. I’m taking the AP World History exam this May and I personally find the content very interesting. There isn’t a huge amount of work involved and the content isn’t based on specific dates, just general time periods and concepts from those periods (example: periods the Chinese Dynasties ruled, their impacts, religion, etc.). If you’ve ever taken AP US History it’s less work than that, but a little more that AP Human Geography (depending on teachers). Hoped that helped!