QUESTION: I want to use first person point of view for my hero, and third person for my other characters. What do you think?
As a rule in popular fiction, you don't switch from first to third POV or vice versa.
Some writers have done this, but many readers and reviewers don't like this because they find it so jarring it knocks them out of the story.
This would be a particularly dangerous for a newer writer who doesn't have the experience and control to handle these changes or the reader's trust that they know what they are doing.
I can't suggest which type of POV to use. Only you can decide on that. Consider your comfort level with the different viewpoints, and the ease of telling the story with that POV.
With first person, you must also be certain you can hear the main character's voice well enough to stay in that voice for the whole novel.
If you do decide to write both first and third POV, you should have a very particular reason for it.