Obviously making sure your on-site is bang on is really important.
So assuming that, then moving onto off-site seo - depending on your KWs, web 2.0s aren't enough to be ranking high up the serps. So, what next? I would have said PBNs are a good option if you buy from reputed sellers (there are some here on BHW for example), but given Google's latest crackdown on PBNs with loads of sellers getting their networks de-indexed, then unless your site is something you can afford to lose, I wouldn't take the risk.
So in that case, a self-owned PBN (whilst avoiding footprints) is a decent option to help boost your rankings. Initial outlay is not cheap however.