It sounds like he has a good team, so I would suggest asking for an IEP meeting. Regardless of issues, it's always a good idea to have a meeting during "transition" times, such as transitioning to middle school. All the things you suggest are very good, but I would ask the team to put them in writing under accommodations on the IEP document. Afterwards, touch base with ALL of his teachers (or at least the ones that did not attend the meeting) and make sure they have seen and understand all the accommodations, ask if they have any questions, etc. Be nice, but get it on their radar that he struggles and needs these accommodations.
As for accommodations, go to Lisa's website and look at her recommended accommodations for both ADHD and ASD. Specifically, I would ask for the following:
1) Student will spend no more than 1 and 1/2 times on homework than his peers.
2) Shorten assignments once mastery is shown. (For instance, if he understand the math concept being taught, only have him do the even problems for his homework.)
3) Extra time for assignments - 2-3 days in a common accommodation. (I would also ask for this on tests/assessments - both classroom and standardized.)
4) Chunking of assignments and instructions.
5) Frequent check-in's for understanding and being on task.
6) Device for typing for written assignments and assessments.
7) Speech-to-text for written assignments and assessment.
8)Oral assessments in place of written assessments.
I happen to be in KCMO and give one free hour of consultation, if you're interested.