The commonly-thrown-around figure for comparing contracting work to salaried work in the US involves multiplying the salary by about 3x to reach parity, since you have to pay your own employment taxes and health insurance, and to account for sometimes not having a full queue of work.

I guess that in the EU (and maybe .ch / .uk?), you wouldn't need to pay for health insurance as such, and I don't know whether they have this (barbaric, imho) notion of employment taxes, so maybe the number is closer to 1.5x, which would make 180k€ into 120k€ equivalent, which sounds quite good compared to OP saying that typical offers are around 1/3 of what they're making now.