GSA still working good for link building, but for good links use as Tier 1 you must need to see this
tutorial.
Or
this tutorial which is great.

Been working on that since last week to mix with my PBN.
As for software I'd say....
1) GSA + CB (as already said)
2) Scrapebox.
3) Keyword bot! This is commonly left out but a custom keyword bot can be the most valuable tool in your arsenal. Popular keyword bots don't really teach you how to think outside the box. But if you learn to a unique keyword technique for finding great keywords. You can automate it to your needs and it'll pay off in spades.
4) Indexification.
5) VPS.
6) Serpbook / Serpfox
7) Microsoft Excel. I was taught to use this in college for statistics calculations & data engineering. Any marketers who don't know excel, learn it.
8) Photoshop. Took like 3 years to grasp but once you do you'll never outsource designs again.
9) Power Director. For video creation I love it. Adobe After Effects is too damn complicated.
10) FL Studio rewired w/Reason. 14 years now. I don't expect marketers to be musicians. But I'm still shocked by how many marketers don't GAF about sound. They don't care about their voiceovers. Don't care about mastering anything. Don't care what can be done with soundbytes, pitch correction, overdrive, noise gates, NLP anchors. Maybe I'm weird in regards to video, but I've always "seen sound" as the dominant force. Just try watching porn without sound. Why do you think pornstars are taught to make dirty noises? Slurping sounds? Would you rather see a quiet 10 BJ or a slurpy 8? Ever notice that all the best movies in the world typically have great soundtracks? Not just great soundtracks but great voices and fx that are used the right way? We have databases full of research about the effects of sound on emotion. When I hear an ad on the radio with a phone ringing at -38 DBs, a sound an untrained ear will not recognize, I know that mfkr is trying to trick me. I know why that sound wasn't meant to be "heard". I know why it's repeated 3 times in the commercial. When I hear a specific word or phrase being flanged, stretched or detuned over and over... I know it's a buy pattern. I know what that person's trying to do.
Anyway, that's the software I use.
-BB