In my opinion all recreational drugs, whether soft or hard must be legalized. An individual should have the freedom on what he should do with his body. The state has no control or responsibility here.
I agree. But the problem is that after decriminalization
state will be tempted to repair its ailing finances by taxation
of these drugs. Which implies monopolistic control of them.
So the ideal solution is decriminalization coupled with moralistic
mainstream attitude towards drugs on the general public level,
that makes it hard for the state to interfere. We then have a
thriving underground culture that benefits everyone

I don't think this is totally accurate. For me, I'd prefer a system where commercial marijuana is taxed and regulated (just like commercial food production) but allow people to grow and barter their own on small scales without interference (again like cottage industry food production).