Thank you for the in-debth response.

My spouse is on board emotionally, we've talked thoroughly about it. Health insurance stuff will be taken care of if I do quit and is baked into my calculations (as is VAT, taxes, etc).

I start networking and pitching actively to my contacts for work/ the day after I resign, which means I'd have three months left in my job to find clients/contracts before I started working on my own - standard notice of resignation in my country is three months.