Taking the Early Withdrawal Penalty

I've been slowing down on work lately, and had planned on it being a slow process where I could accumulate more savings during my low income years to use while getting a Roth Ladder Conversion going. Fortunately or unfortunately I'm really enjoying all this free time, and find myself putting in less and less work. I'm very heavy on my 401k and would like to start accessing it early.

I have about 700k in my Taditional Solo 401k, 15k in an HSA, 50k in taxable brokerage, 150k in home equity (~800k value), and my home is a duplex so I get rental income from the other unit. In retirement I plan on earning about 10k a year from various hobbies. I'll need to withdraw about 40k a year, and that will cover business expenses, taxes and withdrawal penalties and all that - I can reduce my personal spending to cover them if need be. I know that at 4%, I can currently only withdraw about 30k, especially given that I'm only 35, so I have a few more years I need to push on, but I don't think I'll be able to get to the ~$200k I'll need to start a ladder, since I'm basically coastFI now.

I could just do some conversions now, but that would bump me into the 22% bracket, which would take away a lot of subsidies. It seems to me, that just taking the penalty would result in the same as the 22% taxes (12% tax bracket + 10% penalty). I considered SEPP, but that would take my entire portfolio to give me the amount I need, and that lack of flexibility for 30 years unnerves me. I'm going to try to earn that extra bit of cash cushion, but I fear my willpower is fading. Thoughts?