I don't think Democrats should waste their time on any impeachment votes at all for several reasons.
1) It would be a wasted effort right now because Republicans aren't going to vote for it right now.
2) There's so many investigations into Trump right now that it would be best to wait for all those investigations to conclude so that the facts from those investigations come out.
Depending on how overwhelming the facts are, Republicans may sign on for impeaching the President. However, if they don't sign on for impeachment, then I think the best way for removing Trump from office is at the ballot box in 2020.
1) It would be a wasted effort right now because Republicans aren't going to vote for it right now.
2) There's so many investigations into Trump right now that it would be best to wait for all those investigations to conclude so that the facts from those investigations come out.
Depending on how overwhelming the facts are, Republicans may sign on for impeaching the President. However, if they don't sign on for impeachment, then I think the best way for removing Trump from office is at the ballot box in 2020.