This investigation probably isn't over until at least May. Could be by the end of the summer. I remember Eric Holder saying this would be 2 year case.
They are still subpoenaing witnesses, Manafort won't give up passwords to certain things so there's still information they are missing, the mystery case that is probably a Russian bank is held up in the supreme court, and I don't recall there being a story saying Mueller is going after Don Jr's contacts with Wikileaks. (Don't mean he hasn't been looking) In theory Don Jr should be the last one to be indicted.
It's hard to have patience to wait that long when the longer this goes on, the more likely Trump finishes his first term.