For me, I wish school had been able to put in a lot of support as soon as my DD started struggling to attend. I felt like it was all the wrong way around - once it had completely unravelled, they started offering some of the support I'd asked for at the beginning but it was too late by then. It all came down to lack of resources. Which is ironic given that she's costing a lot more now as a result (EHCP, PIP, CAMHS etc).
I also feel there is a desperate need for small, predictable schools/colleges with for ND children/young people who can achieve academically (whether that be to a greater or lesser degree) but who just cannot cope in a mainstream environment.
Going back even further, I wish supports had been put in place for my daughter early on when for example her sensory difficulties and OCD were first identified. I also wish someone had suggested autism to me early on when I raised her difficulties, rather than letting her fly under the radar because she was the model pupil or because they didn't like to say. This relates to health services too, not just school.
So basically, improve outcomes for the child (ideally with early intervention) and you improve the outcome for the parent/s in terms of being able to work.
Counselling for parents would also be gratefully received as it's a lot to process when things finally fall apart so spectacularly. The day to day stress of caring for your child and fighting for services makes working (especially in a high stress role) hard to cope with at times and an outlet of some kind is definitely needed.