I see no reason not to criminalise sex buyers, and I'd go further e.g. on a second or third offence they go on the sex offenders register or names and photos are somehow otherwise publicised.
I'd also like to see pornography moved back into the realm of the 'dirty mac' man, or the 'once in a blue moon at a stag party' sort of thing - IP blocking of the porn and streaming sites like they did to the filesharing sites would be a start. Coupled with robust education to all that porn and the sex industry is damaging not liberating, and that together our society should aim to minimise rather than normalise it. (Not in a prudish way either - we should still celebrate sex and love - but we acknowledge there's a dark side to it and 'anything goes' isn't the right approach.)
Basically make it harder for men to do this sort of thing, force them when they do do it to have to take active steps to circumvent norms, so it's clear when they do it that they're acting antisocially. And make it a genuinely risky endeavour for them.
What you do with the women involved is a much thornier problem, I do see that. 'Helping them get out' is much easier said than done, and I can well imagine 'preferring' selling sex to a low paid job. Though I think on balance the low paid job would be better for a person's long term survival, mental health, social success and so on.
If you're going to adopt a model where the sellers of sex are not criminalised then it's an all or nothing thing. You can't say it's decriminalised but then quietly continue arresting women for working together, or for 'selling sex while being an immigrant' or whatever.