I 100% agree that the new Broly feels a lot weaker than the original, which is odd because logically I know this incarnation of Broly would likely make mince-meat outta the old Broly. It's weird how the new movie kinda missed what the original appeal of Broly was, the overwhelming dominance he had. Effortlessly annihilating a group of Super Saiyans feels a lot more oppressively strong than just being on a level playing field with Goku. Not to mention, he like what, beat up Frieza for like an hour straight because they kept messing up the Fusion Dance and Frieza survived that fine?
All that said, I far prefer the new Broly. I prefer actual character to mindless monster whose entire motivation is that baby cried really loud next to him, and I think the new version of Broly did a great job of allowing Goku's character to shine, my favorite moments of the movie that didn't involve Frieza being an absolute troll, were in Goku's interactions with Broly, early on telling him that Broly didn't feel like an enemy & the fight was over and the entirety of the ending scene with them, both great showcases of Goku's character (perhaps the best scenes at expressing who Goku fundamentally is, a kind-hearted person with a hard-on for fighting). And the movie itself is second only to Battle of Gods for me. I'll trade Broly's sense of power for stronger character dynamics every-time.