Currently, I have many links on pages with content (articles). Would I get better ranking in SERPs, if I'd remove the unnecessary links? What's your opinion?
Not really. Some might argue loss of pr would hurt, but in reality it's good to link to relevant resources, even more so if you can link to relevant resources within your own site.
Why is it good to link to relevant sources? I mean from a SEO perspective... Obviously, the visitors will appreciate to be informed of other sources of relevant information, that for sure...