You know the bit about when all you have is a hammer, everything is a nail? I was like that when it came to POV and perspective. All third person. All the time. Critique partners kept commenting on how distant my characters felt. Looking back, it's easy to see this was the price of suffering untreated, major depressive issues as a teen - everything happened at vast emotional remove, you know? And even though I'd finally been treated, the habit of emotional remove had stayed in place. Hardly conducive to a writing career. But I desperately wanted my stories to WORK. I just didn't have the emotional vocabulary to work out how to close the distance. It wasn't until a local, RWA meeting where the incomparable Stella Cameron looked me in the eye and explained that third person omniscient kept readers outside of my characters - something utterly incompatible with how romance works that the light bulb switched on in my head. I had a problem. I had to solve it come hell or high water.
Suddenly, every last thing I'd ever spent waaaaaaay too much money learning at acting school came back. I knew how to turn myself into someone else. It said so on my degree. What I hadn't known how to do was turn myself into some distant he or she out there in the ether. Another Stella - Stella Adler once equated acting with playing what if. The great actors, she said, didn't make themselves into someone else, they asked 'what if I'd grown up with this background, were faced with this dilemma, this obstacle?' and they respond from within themselves.
Drafting in first person unlocked that for me - though I won't claim any sort of greatness - just a deeper level of understanding how to get readers into a character's emotional life. I hope.
However. I still have a first person bias. Only one piece (Emissary) ended up published in first person. All the rest were transcribed from first to third. The greatest compliment I ever had was when a critique partner complained when I brought a WIP that had been switched from first to third - she said, "Are you sure you want to make this switch? I miss the heroine." You see why I love my crit partners? Thing is, I'm still writing romance and third person gives me the most flexibility in getting the hero and the heroine some time on the page so readers can see from both points of view.
These days, I no longer have to draft in first person. If a story is particularly challenging, however, it's default. A kind of cheat I use to remind myself that it's about the feels, silly! And about a character's unique filter on whatever experience they're having. Drafting in first person seems to let me step around myself in some odd way and interact with a story with fewer hang ups. Dunno why. I'm sure there's some deep psychological and possibly disturbing reasoning there. I'm not sure I want to know. After all. The first to third seems to be working.