Every writer wants to be fresh and different to stand out from the pack in this competitive industry, but using an unhinged narrator or waffling narrative style is NOT the way to go right out of the gate. You need to have a very good grasp of Narratives and adeptness in each before you can use First and Third in one work. With First Person, voice is the most important thing. It's not just transferring He and She to an I perspective; it's about delving in deep and exposing an engaging character, giving readers a more intimate look. To avoid having flat and lifeless drones, you must become a master of voice.
I've read some unpublished works that have a few chapters in First present, then chapters in Third past inserted wherever. Or 95% of the book is Limited and a few sneak peeks go all Omni. Wait. Settle that crazy pen down, Buckaroos. This is jarring to readers. Aim for seamless, easy, functional, entertaining, readable work. If your narration jumps all over the place, it won't be any of those things.
Everything you do as a writer needs to be deliberate and focused. Using fluctuating Narrators is not unheard of but you need to pull back the reigns a bit. Instead of looking unique, you are at risk for coming across as inept and scatterbrained, like you have no clue about perspective. That's not the impression you want to give.
This is an example of a focused, deliberate switch: using a Third Person Frame that connects First Person Vignettes. Say you're writing a book like The Green Mile and want to delve into the head of each character right before execution. With proper transitions, readers will know, okay, each time "Dead man walking!" is called, the story's going to shift into First. Or you could have characters around a campfire sharing freaky real-life stories or alcoholics at an AA meeting or a couple at counselling. The Third Person Narration keeps everything tied together. It works. But just having this chapter Third, the next two First, the next three Third, plus, tense changes is very confusing and jarring. Don't do this, please.
And then there's the head-hopping Narrator that breaks out of its Limited shell suddenly in chapter 5, sneaking in something that's outside the knowledge of the POV character. What? No. You can use a tightly reigned Omniscient Narrator that sticks with one character per scene and interjects commentary here and there that the focus character doesn't know, but this type of Narrator must make its presence known in the first sentence or paragraph of the work.
I just finished Needful Things. Stephen King used an Omniscient Narrator, made it known in chapter 1, but 95 % of the time kept the focus on one scene character. You can vary the degree of intensity into heads or the focus, staying more so with one character or roving constantly. As long as you provide clear transitions and separate new perspectives with new paragraphs, you can generally keep it from being jarring. But you'll need to go fleshy and get extremely deep and with character development so readers will care about the outcome and enage in the story.
With Needful Things, which had dozens of POVs, I struggled to finish those 800 pages because the characters were cardboard and I didn't care. I wanted to see how it resolved, but I didn't care about any of the characters, I didn't care if the villain won in the end. So make the extra effort to make your characters pop off the page with engaging personalities and perspectives.
Random switches whenever you please is unfair. You make a contract with readers in chapter 1 that you're going to tell one kind of story, and any departures from that established mode breach it.
If you're going to do anything unusual, then you need to set patterns and keep a very rigid structure. Alternate every other chapter, for instance, or use First in chapter 1, the next two in Third. First in chapter 4, the next two in Third. Keep yourself locked in to a definite method to avoid confusing your readers. Use good transitions. Give cues that you're about to change gears. This will demonstrate that you know what you're doing and you're not just flying with the wind or riding on a pogo stick, doing whatever you please.
If you really want to be weird and original, then aim for a unique concept instead. Have quirky characters. Take your plot in unexpected directions. Build in some twists. This will get far more attention and recognition than skipping around with haphazard zest ever will. If you're all over the place, you won't look original, you won't look creative, you won't look fresh-faced...just crazy and stupid. And FYI crazy people get much smaller checks. Make sure your Narration is focused and that you're telling the story in the best way possible.
~ Signing off and sending out cyber hugs.