O1 is overrated and not that useful. It still needs to be sponsored by an employer, and the employer will make the determination if they want to sponsor an O1 for you. It's mainly useful if you can't make it through the H1B lottery. The criteria are subjective, but it's a lower bar than EB1A. Look at AAO decisions to get a sense of what gets rejected. The general framework for how USCIS looks at these is based on case law from Kazarian, which states that you need to satisfy the numerical criteria as a 1st step, and there is a final merits determination as a 2nd step. This was for EB1A, but USCIS also uses the same framework for O1s (although there is some litigation going on on whether Kazarian should apply to O1).