Meghan and Harry:
It's a long-term strategy from me and so a hopeless case as they don't seem to be able to manage something like that.
This year: Consolidate all the non-profit Archwell stuff as much as possible, pick a decent manager and let them run it as a foundation managing current donations for chosen charities, fundraising and being generally background supportive for a few specific areas of concern.
Sell up on the West Coast - get away from the shallow drama of Hollywood and move to the East Coast - get a nice private, modest, and easily secured house just outside New York (think Ryan Reynolds and Blake Lively's set up).
Stop briefing your friends and the media against your family members.
For the next five years, heads down and do something substantial that doesn't require any publicity. Harry - get yourself one of the paid director positions that rich boys get and split your time between that and one volunteer position for a charity that actually requires you to turn up sober on a regular basis and physically do something. Plant trees, clean rivers etc etc.
Meghan - pick one, just ONE cause and go back to university and get a Masters or PHD in it. Social justice, women's rights, internet safety. In your spare time also commit to one charity which requires physically doing something on a regular basis - packing bags for homeless children, or an acting school in an underprivileged area. Do it with NO publicity from your own team.
Quietly and privately spend at least one vacation with Charles in Balmoral every year.
Put the kids in an international school system so that....
In five years time - 2030 - when Archie is ready for secondary school move back to the UK so that Archie and Lilli can get to fully experience their UK heritage.
Use the previous five years of hard work and knowledge gathering to set up something substantial connected to your chosen area.
You will have shown patience, commitment, conciliation and restraint - British public will probably get on board with the new you, Charles will be relieved and I'm sure loosen the purse strings a little again. William may not have forgiven you yet but at least you won't have made him any more mad so might have saved a chance to get your pension from him in later years.