I definitely agree about moving as many nebs as you can to inhalers. I remember when my daughter was that age, and it was REALLY difficult. I thought it would be that miserable forever, but it did get better. Getting a consistent routine that he can depend on (as it seems you are trying to figure out) will definitely be necessary.
Our night times go like this:
after dinner is bathtime.
After bath, we set up the nebs. I let Alyssa help as much as possible, this way she knows what's coming and its made it easier to get everything going. While we put the med in the nebs, etc., we discuss what we are going to do during treatment time.
Treatment time is Alyssa time. She gets to decide what we watch or play and who she plays with. Some days we watch a movie, some we play a game on the ipad or cards. When she was too little to play cards, we did puzzles or colored with crayons.
Treatment time is non-negotiable. She has control over what we do WITH the treatment, but the treatment itself HAS to happen. If she wants it to be fun, she'll choose not to melt down or cry. If she does cry, I'll just hold her down and hold the nebs on her.
It SUCKS, to have them cry through the nebs. But if you just stick to it, he will eventually resist less and less. Eventually he'll sit there and do what he needs to.
Hang in there....he'll get there. At first he'll fight every day, but soon it will be every other day, or every third day, and eventually you'll forget that he fought the treatments every day. We still have an occasional meltdown over treatments, its not a perfect system, but its sooooo much better.