I don't think there is, I think, if you take biases out of the equation, you don't get to where you NEED to be for impeachment.
You have Trump asking Ukraine to investigate corruption and specifically mentioned Biden, on a phone call. You have Sonderland stating that the President was apprehensive about giving the aid to Ukraine, DUE TO WIDE SPREAD CORRUPTION, this was BEFORE the call. You have Trump giving the aid before any investigation is opened at all, and you have Ukraine stating, that they didn't know the aide was held up, and the President of Ukraine stating that he didn't feel any pressure.
I think the bigger issue for Trump, is China, the comments he made about China and Biden, crossed the line as the comments he made before during the campaign about Russia, did not. Russia and the campaign etc, he was joking, playing to the crowd. Can't make that same argument about his request of China etc....