I do all of that but not much low quality stuff (spam) anymore. Parasites can be good for filler but I don't expect them to stick around on the first page long term. They're often good for pages 2 and beyond. I always try to get an EMD if possible, it's a long term strategy but can pay off very well. If you can get an exact match and a couple partial matches that helps as well. I tend to focus on buying .com's rather than an EMD .net/org/info as the partial match .com ranks better in my experience.
For link building it's all about testing. I spend a lot of time and money every month testing various types of links as well as strategies. What's working now won't be working a year from now so you need to always be focused on common sense (is this a good link?) as well as testing to see if it's effective.
PBN's can be good for that but they're not often a great long term strategy because people let the domains or hosting expire. Building your own is best in that regard.