There could still be a censure of Trump with real legislative teeth in it, perhaps in conjunction with section 3 of the 14th Amendment (which would prevent him from running for office again). This would only require a few of the seven Republicans who were willing to convict regarding impeachment to vote to censure Trump in a serious, meaningful way.
This strategy is actually politically possible and I am continually updating it as events evolve in The War After the Election https://medium.com/illumination-curated/the-war-after-the-election-545de96aa4ca?sk=627c55d616d9296af3e398f1686493a4 and in a short link at the end of it which explains the very targeted, but critical legislation that could be attached to the censure.
We must take a long-term view, because as you indicate an impeachment conviction wouldn’t have solved the problem. But people need to become more active than just “voting”. Democracy requires participation at more than just the ballot box. It requires citizen participation BETWEEN elections on many levels. The legislation at the end of The War After the Election is a good start, and I will be developing this approach as events evolve. Also, everybody should read the entirety of Ed Blosch’s response to this article because it also contains some very good ideas which need to be considered.