I don't host my family tree on my own website, but those I know who do, have abandoned other sites such as Ancestry and just host their own version which they have complete control over.
It depends what you want to gain from making your tree public. Keeping a tree on Ancestry has its pluses and minuses.
The best way to keep the same information in more than one place is to keep it in GEDCOM form on your computer, and upload it to each website periodically when more information is added.