My current backlink strategy

Here is my current backlink strategy. Critique it and add to it:

1. Guest Blog posts: It know it's greyhat, but it works. I check the backlink profile. I check the ranked keywords. I make sure the site is one that people actually use and isn't just a PBN or an SEO backlink site. Has worked very well for me.
2. Leveraging guest blog posts into secondary outreach backlinks: Since I'm already buying guest posts, and those guest posts usually let me put 2-3 backlinks on an article, I offer one of those backlinks to a relevant site. This way I can get 2 backlinks for the price of one.
3. "Jealous link building strategy" - Stole this from seonotebook. Do backlink outreach and leverage competitor's articles. Let them know that we can write a better article and steal some traffic for that keyword from the competitor. Has only worked a hand-full of times. Lemme cook.
4. web 2.0 links - I know I'll get roasted for this, but I work with a lot of low DA sites with small businesses. This works for us. Not for everyone. But for us, it's been beneficial.

Tell me what you think!