Therefore, the evidence will not be limited to the president's speech but every utterance he ever made and every act he ever undertook in office will be adduced in support of that proposition. Most important, the assumption will be made that the mere questioning of the count of the election is in itself incitement to riot or somehow a crime against the Constitution.
Further, the incident will be attributed to white supremacy which of course is the most toxic charge, even if not one of the bill of particulars.
The the president's defense obviously will be to point out the moderation of his speech especially the phrase when he exhorted the crowd to " protest peacefully and patriotically."
Before they get to that there will be motion practice, the president's team will move to dismiss because the president is already out of office. If that does not carry the president's team will move to limit the charge to traditional incitement to riot, not opposition to the count.
If the motions fail, it is in the president's interest to have an extended trial to demonstrate that it has been the tradition in America to question the count and to do that by quoting, preferably by video, leading Democrats who have already done that in previous elections.
Finally, it is in the president's interest to have an extenuating trial to raise as an affirmative defense all of the dubious efforts by the Democrats to impeach him and to prevent him from taking office since 2016, to point out that there were plans by leftists to riot etc.
A short trial works to the advantage of the Democrats and Mitch McConnell, Donald Trump needs a full hearing to get on the attack. This is after all not an actual impeachment but a Soviet style sham trial rigged for the cameras.
Mitch McConnell will collude with the Democrats to foreshorten the trial, deny actual witness testimony, and require the entire matter to be argued in theory rather than proved in fact. All of these restrictions operate against Donald Trump.
With advocates like Mitch McConnell who needs prosecutors?

Agree with your thesis. Mitch and his rino members want to restore control of the Republican party for their own objectives and vanquish Trump.
Here is my theory as to the events of January 6. Trump supporters have planned to stage a rally in the nation’s capital expected to draw 10s of thousands on the day that Electoral votes are to be counted/challenged in Congress.
In addition there is widespread fear that there will be far more Trump supporters than Biden fans at Biden’s inauguration. This would, of course humiliate the new President. How to stop this from happening?
Have agents provocateurs “storm” the Capitol followed by some Trump supporters caught up in the moment carefully staying between the rope lines. Trash a few offices, break a few windows etc. They are cleared out fairly quickly. This accomplishes three things.
The vote challenges are quickly dropped, remember that originally there were to be challenges to each of the swing states, but only one occurred after the ‘riot’.
Trump is instantly impeached in the House for attempting ‘insurrection’ with 10 republicans going along with the idea that a President can lead an insurrection against a government he leads. If he’s convicted by the Senate, he can be barred from running for any Federal office, thus permanently killing the Trump threat to the swamp.
Although the Wuhan virus was going to be the excuse for small crowds for the immensely popular Biden’s inauguration, now 10 of thousands of troops can be brought in the the capital because of the “real threat of insurrection”. No embarrassing moment when large crowds boo Biden as he takes the oath.