The biggest problem with Res F is that they gave Vegeta only 5% of the fight sequences and didn't even let him get the killing blow. I swear to god they better let Vegeta be the one to destroy Freiza this time or else they've screwed up bad again. After 30 year's of Vegeta's existence as a fictional character he still barely has any kind of closure to his origin story.
The biggest problem to me was mostly that the whole movie had no reason to exist. It felt like filler. It told largely a pointless story where at the end of it everything goes back right to square one. As a result bringing Freeza back for that movie felt like such horrible fan service and nothing more. That movie was so bad especially when you start comparing it to Battle of Gods.