Making a 301 redirect from expired domains

[moppy]

I have been working a lot on content of my site lately. So, I decided now to build some links. I have got some old domains which I have purchased they are good and have 30-25 DA more or less. And to them there are also some good backlinks linking from sites which have good authority in my niche.

Now here is the query of mine. Should I 301 redirect the old domains to my main site. Or create some content in them and then lin back to my main site. Which one will be the better option for me?