I recently read Allegiant, and I honestly really liked it... for the most part. I for sure liked it a lot more than I liked Insurgent, but not as much as I liked Divergent. I really like the characters, but I don't think there is much character progression. In my opinion the characters just don't seem to have changed at all from the first book.
The plot was good I liked how the story progressed. It was really fast paced and I didn't want to put it down. I finished the book within a couple of days. For me, there wasn't really a dull moment in the book.
Now... about the ending,(SPOILER SPOILER SPOILER) I can't believe that Tris died. I did not like that, just ask the people who had to hear me repeat for five days "I can't believe she's dead. The book overall was enjoyable, but I just didn't like that, that was how they decided to end the trilogy.