Depending on where you are staying, it might take a bit longer or be more expensive to get to your hotel as they will close Storrow Drive and taxis frequently take that to Back Bay hotels. So, just need to be a bit patient.
Things like Duck Tours (lots of fun) may well sell out so should check on that and lines at the USS Constitution will definitely be longer. But, the Freedom Trail itself is so spread out that there's no reason not to do it. Faneuil Hall will be more fun than usual.
For the fireworks, the Longfellow Bridge will not be an option due to construction. The Cambridge side of the river by MIT is a good place to watch and they pipe in the music.
Overall, a lot of locals will clear out for the weekend to higher end restaurants should have some nice availability.