Thanks much. That is my impression as well.
If it is actually constitutionally incorrect to have a post-presidential impeachment trial, then let the Senate make a formal declaration to the fact via the current Trump impeachment trial.
And regardless of what the Senate has to say about the matter, one way or the other, then Trump should be arrested, tried, convicted and imprisoned for the riot he caused. Also, Trump should be on the hook for the millions of dollars in damages that he caused by his incitement of the riot.
By the way, I would expect that all of these legal troubles plus the numerous financial issues that Trump is now facing with his various creditors, then Trump is now in the most trouble that he ever has been.