A thoroughly mediocre movie - might disappoint existing fans by targeting a broader and younger audience

Rating: 4/10 (17 December 2017)

Warning: This review contains significant spoilers.
After the excellent Rogue One and the very positive reviews that this movie received, I was hopeful that it would be outstanding. However, I left the theater with a feeling of enormous disappointment. Let me start with the positive aspects of the movie, though. Technically, it is a masterpiece: the special effects are fantastic. Visually, it is a stunning recreation and advancement of the original Star Wars trilogy (Episodes IV-VI). Most of the actors do a good job and the soundtrack is great, too. The space battles are extremely well made -- probably the best I've seen in any movie so far.
However, all of these positive aspects cannot save the movie from its poor plot, misplaced humor, and the fact that it simply does not feel like an authentic continuation of the existing Star Wars universe. Obviously, the last point in particular is subjective, but below I will provide detailed reasons for my judgment.
In general, the plot is not believable, tries to achieve too much, and delivers too little at the same time. It is not credible because the entire story feels forced. The uninterrupted hour-long hunt for the Resistance ships (which is a very thin and weak main story line) seems like an artificial way to create tensions. It is full of gaps and developments that are not believable. On the one hand you have the technologically vastly superior First Order forces which are able to follow the Resistance fleet through light speed (something that, according to the characters in the movie, was not even possible previously). On the other hand, they are not able to get any closer to them when in normal speed. Also, it is not believable that an explosion that destroys the entire bridge of a ship and kills everyone on it, leaves Leia physically mostly unharmed (not a Jedi trick, because the Jedi can definitely be harmed physically). Furthermore, the fact that the one person they absolutely need for their plan (the so-called "Code Breaker") is conveniently close to the location of the chase just appears to be too big a coincidence. Similarly, the presence of a comparatively close old rebel base is not very credible either. Finally, Supreme Leader Snoke, who appears to be a mastermind, does not notice the light saber next to him turning (I mean, come on)...
One of the biggest problems with the plot is that the tensions created are resolved much too quickly and in an anticlimactic fashion. Supreme Leader Snoke, who we barely know and who remains completely mysterious, is taken out of the movie after approximately five minutes of conversation without any big fight. He turns out to merely be a placeholder to fulfill a certain story function. The problem that characters are introduced too fast, remain underdeveloped, and are then removed (even though there is great potential to develop them) -- like Captain Phasma or Rose Tico -- shows that the movie tries to achieve too much but delivers too little. While the plot heavily focuses on Rey, Kylo Ren, and Luke Skywalker, nearly all other characters suffer a fate of under-development and/or quick removal.
Also, actors throw around the word "treason" and even commit acts of betrayal without any meaningful consequences. For example, Poe Dameron takes over the command of the Resistance in a "coup d'Ã©tat," only to apparently be forgiven shortly afterwards. This is presumably due to the movie's younger target group, but doesn't help its authenticity at all.
This leads straight to my second major concern: Episode VIII simply is not an authentic continuation of the existing Star Wars universe. The development of characters and the main story was much more believable in the old Expanded Universe that is no longer part of the official canon. Just compare the development of Luke Skywalker's personality in the old Expanded Universe, as a guardian of new Republic and heir to the Jedi Order, to his completely new personality in Episode VIII (where he runs away from everything and tries to destroy the legacy of the Jedi). Considering that throughout Episode VI Luke does not give up the hope of turning the evil overlord Vader (who he knows to be his father) into a good person again and in light of his success at doing this, it is also not credible at all that he would even consider killing his nephew -- Kylo Ren -- in his sleep. It just doesn't make any sense given Luke's previous character development.
As pointed out above, Snoke's appearance and development is also more of a joke. Not to mention Kylo Ren: with his childish attitude he simply cannot serve as a credible bad guy (and especially not Supreme Leader). The entire First Order is a cartoonish version of the Empire. This is not Star Wars anymore. Moreover, the casino scene and the entire side plot with Finn and Rose also did not match the atmosphere and world design of any previous Star Wars movie. The casino looked more like Las Vegas than anything I've seen in the Star Wars universe so far.
Finally, the humor used in the movie often feels misplaced. The film seriously starts with a "prank phone call" from Poe Dameron to the general of the First Order. This reminded me of Bart Simpson's calls to Moe's bar and just feels completely wrong as the opening scene. The First Order commander is fooled too easily and his behavior and attitudes remind me more of a teenager than of a high-ranking imperial (First Order) officer. This is again presumably due to the movie's younger target group.
Some jokes are pretty good and made me laugh, but their frequency is so high that it simply doesn't feel like we can take most characters seriously anymore. That may be the goal of the creators of the movie -- to produce something more light-hearted -- but, as I said above, this simply is not an authentic continuation of the existing Star Wars universe.
Overall, it is pretty clear to me that the movie seeks the broadest possible audience. With stunning special effects, great space battle action, lots of light-hearted humor, and a more cartoonish First Order it wants to turn everyone into Star Wars fans. However, by doing this, it breaks with previous movies of the saga and ultimately has enormous potential to disappoint existing fans. By going maximally mainstream (more than Star Wars was ever before), the movie might be successful at making money, but it's ever harder to distinguish Star Wars in a meaningful way from any other recent SciFi film or even the latest super hero movies. Despite its strengths, the weaknesses -- especially the bad plot and not credible character development -- make it mediocre overall. If this movie would not have the label "Star Wars" on it, most people would probably not care to see it. It likely would be forgotten within a few years. With the label Star Wars on it, despite all of its shortcomings, it will probably be an enormous (financial) success.