I have an ASD child who occasionally finds it difficult to go to sleep (and was a very light sleeper as a baby), but this week I have sussed out what the answer is. Exercise and fresh air are the wonder drugs. He is so tired he can hardly get up the stairs this evening, after a day in a sports camp of sorts (outdoors)
The other thing is that a pattern very quickly forms in their minds, of anxiety that they can't sleep, which reinforces the inability to sleep, like a vicious circle. So I can see that in a way you are trying to avoid that vicious circle by keeping him up rather than endlessly and fruitless putting him to bed. But there is a middle way.
We found that we had to find a bedtime pattern that worked for us - a routine that he associated with dropping off. To start with it was reading a story, then it changed to just leaving him without a story to look at a book himself, then it changed back to reading him a story, which I found lulled him to sleep quite easily. Water was very calming too. A long bath (20 mins? where he just played around with toys in the water without intervention) Also a snack at bedtime high carb was good, or dairy, and quite clear boundaries of light off/tucked up, goodbye.
He is 11 but I think we have been through lots of stages since he was a baby. It keeps changing. But your little boy is tired, even if he exhibiting wakefulness. He needs sleep, it is just that his brain is wired to wakefulness. Presumably being tired is affecting him in lots of ways and making him stressed and that is why he is getting cross with you and throwing things. It is very frustrating not being able to sleep when you need to. So trying to get a pattern which works, however it works, which will get him to sleep...music, soft toy, story, sitting with him, chatting, snack, (anything really except electronic screens which add to wakefulness) is something that you can work on. And then stick with the routine, routine, sense of familiar events are v important to calm them.
Good luck, you can do it. Personally I never used a reward based bedtime system. I think it upped the tension and anxiety and worry about not being able to go to sleep, and also created a bad feeling between carer and child.