I know that soft money can’t go to hard money.
But can this hard money go to soft money? Can she use it to start a ChristinePAC? Then she could take her show on the road... books, websites, speaking engagements, etc.
I'm not entirely familiar with all the relevant laws, but the short answer is yes, they could convert all that campaign money into a PAC so long as they satisfy some requirements. I'd have to look up the law to say precisely what those requirements are.
Also, candidates can give their left over money entirely to a charity, or partially (with limits) to other candidates or they can save it for future campaigns.