I think you’re probably right in how it will go, QA.

I don’t think anyone knows how Chief Justice John Roberts will run the trial. In all the huffing and puffing about what Senate Republicans will do, folks seem to have forgotten that McConnel won’t get to decide when to vote or how. The Senate trial’s judge is the Chief justice of SCOTUS. That takes the process more out of the political arena and more in the justice one. That’s where you’re question about whether its an impeachable offense might get decided. there will be lots of motions to the court and lots of little decisions.
In my best Chris Berman voice “It could go either way!’

BKB