You can get away with very little.
I have more channels, but for practice I just use BD + OHs most of the time.
If you have an iPad you can probably get most of all the things you want to play to from that. I use Spotify(combine Amazing Slowdowner with that), DrumJam and Pro Metronome.
It's going to change a lot over time.
Personally, I'm not a fan of any of those surfaces, especially mesh, but opinions differ.
If the plan is to play an acoustic kit I'd definetly recommend getting access to that sometimes. A snare doesn't need to be expensive and there's probably a room you...
I got it today.
Basically, it starts off with stickings and basic accent patters + some reading text, but they're written out from triplets to septulets.
Chapter 2 is your mixed subdivision stuff and Chapter 3 is hand independnce.