Part 1, I don't object in this case to the trendy decision to split a saga's concluding book into two movies. I feel that in this case, it allows the films (in principal) to give more narrative weight to the revolution that at times felt like an afterthought in the books (surely not author Suzanne Collins' intent).
That said, I'm not sure the movies really used that opportunity well. Like Part 1, Mockingjay Part 2 feels stretched thin at times, with a few dry and unengaging sections. Worse, the chance to expand on some potentially interesting aspects of the story is overlooked. Why cast Game of Thrones' Gwendoline Christie to play a supposedly powerful military leader when she's only going to have two or three lines in a single scene? Why again squander Woody Harrelson and Elizabeth Banks by barely doing a thing with them?
Mockingjay, Part 2 isn't a bad conclusion to the series. And from what I remember -- which is admittedly spotty -- it's a quite faithful adaptation of the decent concluding book. But it is pretty workmanlike. It checks all the boxes and pushes all the buttons in a deliberate and obvious way. Enough of the sequences do work to make the whole endeavor worthwhile (for example: the subterranean mutt attack is a solid sequence, in moments evoking the feel of Aliens), but many other sequences are a bit old hat by now (Snow's taunting television broadcasts, Gale's self-pity over being second best).
If you've come this far, there's no reason not to complete the ride. But in the long run, I don't think these movies will be remembered for going out on a particularly high note. I give Mockingjay, Part 2 a B-.