Karen,
Not sure what size/model of chair you have -- they are usually sized by height and your heels should not fall off? Larry was 6-1 so we got the MaxiComforter L size but I see they now have a T size that is supposed to work up to 6-8. We also had the "
foot rest extension" which is optional since with Marfan he had disproportionately long legs. That is an extension that only extends as the chair reclines.
Likewise, the neck support differs by model and I agree it should work without augmentation, which the chair really isn't designed for. I don't think PALS would generally benefit from the more convex tufted types; ours is more flat than some.
With loss of core strength, Larry stopped using the chair about the time he started using the power chair, and yes, the wheelchair should support the same comfort, with the right cushion, tweaks and mods like extra foam (including under feet) and laterals/thigh supports if/where needed. So for perspective, he spent 4 years in chair all day and bed for sleep, which I think is fairly common here. Head rest adjustment is also important, as I think often the CALS ends up adjusting it as the neck weakens.