Get some tax advice!!! If you own more than 10% of a foreign company your US taxes become very, very complicated. I relinquished my green card after my first tax filing. If you want to be in the US, found your company in the US.

Good advice. Always get tax and corporate advice. There's no legal issue with going from a TN to a green card but because of the current green card backlogs - because the green card process takes so long - you could be in the difficult position of needing to renew your TN or travel internationally during the process and you wouldn't be able to. So an intervening H-1B is helpful, just not required.

I'm confused. I thought on a TN or H1B I'm not even allowed to start a company in the US.

Your option A involved incorporating a Canadian company and moving to the US. My comment was on your option A. It is extremely painful to own a Canadian company and have USA tax filing obligations. If you absolutely must do this, make sure your company’s fiscal year falls on the calendar year boundary. I found the reporting onerous and chose to stay in Canada.

Oh yeah, for option A I meant to just stay in Canada until my company hopefully gets profitable and then "transfer" it to the US and move to the US if somehow I can self-sponsor/sponsor through company.