You said that you're hosting since 2011, which makes sense since you're essentially grandfathered in.
If you have set up a new system without any reputation now, even if you have set up DKIM and SPF, it's now a lot worse. Major providers like Google and Microsoft won't really tell you, but if you are new but don't have a dedicated AS and instead you're using (for example) Linode you'll be scored lower by having low-cost solutions that just so happens to be abused by spammers.
If you have set up a new system without any reputation now, even if you have set up DKIM and SPF, it's now a lot worse. Major providers like Google and Microsoft won't really tell you, but if you are new but don't have a dedicated AS and instead you're using (for example) Linode you'll be scored lower by having low-cost solutions that just so happens to be abused by spammers.