Like many Dragon Ball Films, Dragon Ball Z Movie 5 Cooler's Revenge is hard to put into the main story timeline and should be seen as an alternative story where Goku beat Frieza and safely came back with everyone to earth.

The movie is about Frieza's older brother who came to earth to restore the honour of the family by killing Goku.
It's a very action packed story with the secondary cast being very active and nobody feels like they exist just because like Goten in the Boo Saga. Despite the short length, the movie really takes full advantage of each second to give us enough time to get to know the characters and their personality. Cooler's henchmen are the equivalent of the Ginyu Force and have some very entertaining interactions with each other and the main cast. They have unique manners and techniques from each others which is why they are more memorable compared your average Dragon Ball henchmen. They show individuality unlike other's that are either reactive or do things as ordered.
The final confrontation against Cooler is set up well too since Goku lost the first encounter and needed to recover until about half of the movie runtime.

Cooler is one of the most interesting antagonist and with his personality being superior to Frieza. While Frieza's selling point was his sheer existence nobody can defy, not even gods, Cooler has the family integrity in mind. In the past, he noticed Frieza letting a Saiyan escape refusing to take care of it himself and predicting that this mistake will be Frieza's downfall.
He is known to analyse the situation showing he is more than just powerful. He noticed that Goku was able to survive his first confrontation and acknowledges the Saiyan's strength being capable to kill his brother.
Cooler also shows assisting his henchmen on various occasion instead of letting them do something and die because they were too weak. And Cooler is one of few characters you can argue deserved the power he has because he is related to Frieza while Frieza was just an overpowered villain pulled out Toriyama's ass without any build up. Something Toriyama and Toei are known for normally.
Cooler's defeat was also one of the best defeats in the franchise to the point it was replicated many times but non worked as well as in this movie. The poetic irony that he acknowledges a fatal mistake he made as his final moment and not having the right to criticize Frieza for his mistakes.

It is the first DBZ movie that features the real Super Saiyan and probably has the best use of it. As it appears as a mystical form that appears in times of despair. Not feeling like just another power up that increases your power by 50 times or something. It became a state that overcomes any hardship presented to it. Unlike what it honestly doing right now.

Criticism that no longer hold ups. This is something I want to mention. And it is about transforming villains. Frieza's first to third form are means to restrict his powers and destructive capabilities. So 4th form Frieza and final form is Frieza's true form. While Cooler was always in his "true form" that should be his final form, but he has a transformation that exist to increase his power. Back in the day it seemed like the writers had no idea how Frieza's forms work and brought confusion to the fanbase. But with the awful Revival of F movie this criticism no longer hold up since Frieza can now also transform like a Super Saiyan to get stronger instead of restraining himself.

Actual criticism. That is the strength of Cooler compared to Frieza. It may be a dub error but many are confused who truly is stronger between Cooler and Frieza, even King Cold. As Dragon Ball Multiverse would show if you read that by any chance (not recommended tho). So many believed Cooler to be stronger in the past, while now everyone believes Frieza was always stronger (excluding the awful Revival of F movie).
There is also a question regarding believability regarding Cooler's henchmen power since they seemed stronger than First Form Frieza. But that can be argued around with Cooler perhaps training them.

If you haven't seen this movie and believe you are a big Dragon Ball fan, you should check it out. You won't be disappointed.