My opinion reminds me of what @Shemac77 wrote earlier today, only the other way around. Usually, a good ending changes my mind on an average book.
Here, I ended up wandering if an unsatisfying and open ending still is worth a »Pick« .
Yes, it is, because the world building and the concentration on the new Union States in Europe balanced it out for me. Additionally, if I am being objective, the presented ending is plausible and fits the plot.