а дальше то что, разве ничего не было?

The only possible context I can inject his into is in the situation of a retired man: "I had a lot to do once. Now I just spend my days sitting in the garden looking forward to the next visit from my children."

What about
You'll have a lot to do once this place is yours
There will be a lot to do once we get back
?

Or do you mean without anything else following?

I mean without anything more following, but your version is perfectly plausible too.