I don't use automation too much. I might be using automation in FL Studio if I need a very complicated process to generate interesting sound. In Linux working with automation is difficult, although sometimes I used seq24 for some automation.
But generally I either use
my pd patches, or I play it live. I also use
kluppe a lot, might use
paulstretch for some sounds sometimes (although generally paulstretch doesn't work well with most sounds, so I use it very rarely).
You can see that a piece like 270 actually consists of a lot of separate pieces. How they come together is a challenge. The better I approach this challenge, the better the track sounds.
The most difficult thing, though, is cleaning up. When you are working with pads and strings and longish sounds, resonating frequencies could be a huge problem. Half of the time you are playing around with equalizers and multiband compressors to remove offending frequencies, this is sometimes very tough work.
Hope that answers your questions! Ask more if you want to know anything else.