I don't have any advice, just wanted to let you know that this kind of crazy happens everywhere. I have 2 boys about the same age and a DH every night, and bed time is still as unsettled in my house as yours. We start dinner about 5pm and if they are both asleep by 8:30pm (hardly ever happens, it's usually closer to 9:30pm) I'm a frazzled mess desperate for a glass of wine. I have to sit by myself for at least 20 minutes to get back to normal... and DS2 normally ends up in our bed about 2am anyway!
I guess that I'm just trying to share to give you some reassurance that 2 parent households also have a tough time with bedtime. You are not alone!