Arguments to move quickly on impeachment

People have been suggesting that Congress is moving too quickly to impeach the President and that we need to slow down and allow the courts to force the Trump Administration to expose still more information. The piece at Reader Supported News makes a strong, but I think flawed, case for waiting.
This piece is behind a paywall, but the summary of the points is
1. "The evidence is already overwhelming."
2. Democrats are trying to "maintain the initiative with the President." That means moving quickly so he can't catch up.
3. The House can keep on gathering evidence right up until the Senate trial begins. That's likely to be well into January, perhaps even into February.
4. Acting as though the evidence is overwhelming is the best way to convince the public that the evidence is overwhelming. The best way to demonstrate that is to move forward quickly.