My first 200m skill I'll be going for is 200m runecrafting. I think it's a super chill skill when doing Soul runes, contrary to popular belief.
I do occasionally try-hard death runes, and bind a ridiculous amount of ess/hr, but I just finished up the last of the pure ess I've gotten from PvM, so I'll be doing souls the rest of the way (that's IF I don't break to kill zulrah if I want to do some death rc'ing). My goal is going to be between 3-5m xp per day at least, with grindy days being closer to 8-9m xp. Keep in mind I'll still be doing farm runs / playing my uim so I might not be super efficient.
Here's the current state of affairs:
Update 2:
Okay I've been going super try-hard this weekend @ soul altar... ~40m xp gained.