I think everyone has different tastes (both personal and also in relation to the types of hearing loss they have) and one of my buttons in particular is when people go out of their way to do everything... except ask what I prefer.
For example, if he prefers to do video chats (I myself do), he may appreciate hand raising/visual cues before speaking (to context switch), clear lighting and dimmer backgrounds (to help lip reading/curing), better mics (basically not anything onboard). Additionally, things like someone taking minutes and recording decisions can be helpful for review afterward to clear up misconceptions or assumptions.
It may be that no matter how many video chat accommodations there are, he may not feel completely included and would prefer text of some kind.
I think another important thing is to make him feel welcome to interrupt or say something outside of the meetings, both implicitly and through explicit reminders -- sometimes it turns out that some accommodations don't work out, or someone is just particularly difficult to understand (accents, enunciation), or something just throws it all out the window (people without cameras, suddenly noisy backgrounds, etc) and it can be hard being the odd one out saying "Hey, this actually isn't working."
I think really though, my strongest recommendation would be to keep him actively involved in accommodations without springing anything on him.
Edit: I want to emphasize that I do think it's great that you're reaching out and trying to help! I just also want to emphasize that for some people, loss of agency regarding how they handle their accommodations, no matter how well-intentioned, can feel bad.