Not a bad idea. Not that most of the media will bother covering it/them - see March for Life - but it does point out that a lot of people are reasonably happy with how things are going.
Turnout is going to be the big problem. Content is not as strong a motive force as rage in the first place, and people on the right of the spectrum do tend to be a little less demonstrative, needing a bribe to rally "for" something or someone. Trump himself, decent speakers, hell, even a funfair on the side would do!