I have 3 EMD's micro niche sites in a very similar topic. None of them is doing good now after all the updates.
I am considering to merge them to one site. So there will be more content on one site.

Is it wise?
Wouldnt i get duplicate content penalty, or something similar?

If i proceed, should i point the old sites to the new/chosen one or just drop them?

Thank you for your opinions.

No ideas?

You can test it out and see if that works. I dont think it will be called duplicate if you will be removing the article from the other sites and posting them in 1 site. All your backlinks might reset to that article as you will have a new permalink for that. Give it a try and and build backlinks to the article which you transferred. Google will index the new link and the old one will get deleted from search.

PS: Its better to go for a brand new domain and transfer all ur articles on a brand new one. Drop off the old domains and delete all the articles on them or maybe just replace those articles on old site with some auto spun content just to show google that you aren't acting dodgy

If your sites have over >30 posts, don't merge.

IMO dont merge them

Simply 301 other 2 domains to the main domain / site which you feel good.

And create new content .