re: DC trip recommendations

Lots of great advice already given.

You don't mention what season of the year, but avoid summer if at all possible. March or Nov would be my choices. That will reduce crowding some. Some museums offer more intimate events (concerts, lectures, etc.) in winter intended for small crowds. Some will be members-only.

Attended a wedding in Old Town Alexandria 2020 and found the water taxi to be a great way to get to the National Mall. Or, you can catch the Metro to much of the Capital area.

Definitely contact your congressman and both Senators. Start by calling their nearest in-state office. Ask for e-mail address of the DC staffer who handles constituent travel requests. Then write that person directly about tours and recs. BTW, not all congressional staffers are from your delegation's state.