It sounds like you're describing my 12-year-old right now. I have many of the same concerns. It also sounds like you've come up with some good solutions. I'll try some of them myself!
This is the first summer where our son is more inclined to sit and watch TV or play with his Wii than contact friends and do stuff with me. He's always been a somewhat emotional kid. And even though he is on the older side of his class, he often is on the younger side emotionally. That being said, I think our sons may both be hitting the hormone stage of adolescence. (Oh goody, right?)
For many years, we have written a list of things we want to do at the beginning of the summer--people he wants to play with, places he wants to go, things he wants to do, things I need to do or want to accomplish, rainy day activities, sunny day activities, etc. It's usually fun dreaming about the summer and all that we can do. And it helps when we're fishing for ideas to do in the summer.
This summer, however, it was really tough to draw this list out of our son. I think there are a couple of things going on. First, he had overnight Scout camp the second full week he was off of school, and he helped with Vacation Bible School the week after that. So he felt like his summer was already mapped out with early risings and that bugged him. Now, we're more into the summer mode and at least that is better.
Second, his feelings about friends are evolving. He tends to be the one to initiate doing things with friends and that is beginning to bug him. He is becoming aware that not many of his friends initiate the calls, and he's beginning to wonder why. He actually said one day that he is waiting for his friends to call to see if they will do it. When they don't, that drags him down. (My philosophy is that they are all sitting at home, hoping to play, but don't have the courage to make the call, so TV and video is easier.)
Our son's friends are evolving, too, not just his feelings about them. Some of his solid friends from earlier years are getting more into sports and he is not particularly an athlete. He is athletic but not an athlete. His closest friends (two of them), he has a delightful time playing with. They can play hours upon hours with Legos, stuffed animals, imaginative play, and yes TV and Wii. They conquer the world 20 times over and make stop action movies with our camera and their Lego creations, among other things. They are great together. But there is still an awareness that his friends are changing and where does he fit into all of that.
Things between our son and I are also evolving. It is to be expected as he matures, but it's driving us both a little nuts with this push-pull thing. Half the time he is his sweet old self, half the time he is this moody, emotional, disrespectful kid. And there's not much in between.
The other day, he was just being a total pisser and, after we both cooled down, I had a brief talk with him. I don't even remember what prompted the anger but we were both angry, and he just wanted me to go away. After a little bit, I heard him crying. When I went in to check on him, he refused to answer. He didn't want to talk about what he was feeling at the moment, so I went back to the kitchen to begin dinner.
After we both cooled down a bit, I let him know that the anger he is feeling towards me is totally common at this age--that EVERY kid (in the country...even in the world probably) feels like this at some time with their parents and that it is normal. (I could tell he was worried that something was going wrong with our relationship--how we could both be so regularly mad at each other?)
The good thing is, after we had this conversation, he thought about it for a bit. And then you know what he did? I couldn't believe it. I was making supper and he voluntarily set up the table (without me asking at all), asked what he needed to do to make salad, and said he wanted to do the rest of the food preparation, and that I didn't have to do anything else! He made it a delightful dinner and I was totally impressed.
At least for our son, he is caught between being a kid and being an adolescent, physically and emotionally. Things are changing in his world. Friendships are becoming more complex. He is pulling away from mom and bonding more with dad and that presents all sorts of emotions he doesn't fully understand. If I can see it all from this perspective, I can maintain my cool. If I get sucked into it, I can be just as respectful back at our son (not my preference). It's a time of change for all of us!
So, with that, know you are not alone. And know that it will pass!
My solution is to get back to limiting TV again. For years, we had had 10 half-hour TV tickets that he could spend any way he wanted per week. We had gotten away from that. We are not strict about the 10 tickets any more. But limiting the TV leads him to be more creative with his time, reading, talking with me, playing Legos, calling friends, etc. It's been better all around.
Meanwhile, I'm going to combine what you've said with what we already do, to approach the rest of the summer. Involving him in more will likely do the trick! As he matures, he is sorting out when he wants more responsibility and when less, and it changes daily! Our expectations of him grow with time but we also are trying to allow some wiggle room so he learns to handle the expectations. Ah, growing up is such a lifetime of grace, angst, and adventure!
Good luck! And have fun with your sons!