You're actually farther into Critical Role than I am; I just finished episode 21 a couple minutes ago. ^~^ But yeah, basically what Harbinger said. Also, you either have (dis)advantage, or you don't. You can't have like 50 advantage factors to get 51 die rolls; it's still just 2 rolls.
On that note, I personally find learning a system to be easiest if I make a character from scratch (or even a few characters), and then play. Some people only need the play portion, since you don't need to know the rules yourself, honestly (though it's nicer to the DM to know them); you say what you want to do, the DM tells you whether or not you can do it, and how to do so mechanically. I mean, even if you know the rules, that's still the case most of the time.
But I'm moderately sure the reason I was holding back from this is...mostly dissolved now? So I could run it, I guess. I don't do anything with voice (because reasons), so doing it on here (since we have a die roller~) is possible. Or roll20. Whichever. If you want a live game, roll20. Otherwise, here, I guess~
If I do run a game for everyone, I'll probably have a DM PC, unless a) the group is absolutely against that, or b) the group is decent-sized (5+) already. I tend to play support roles with DM PCs, so everyone else gets to be awesome. (Playing a healer/buffer/debuffer in my current live game, but we have a party of 3, and we're about to be fighting dragons at level 3, with one person who has only played DnD with us so far, and all of us new to 5e (I learn quickly, and 5e is super easy to learn once you have a handle on it, especially compared to 3.5 and Pathfinder), so...yeah...let them do their awesome sorcery and thievery).
I promise, I'm more coherent in-game. O_O
Edit: Also, I enjoy creative uses of things (like when you've seen Keyleth use thorn whip for stuff, because I have yet to see her use it as written).
Technically the same edit: Dreamscarred Press liked the homebrew conversions of their stuff I posted on Twitter and said it was "pretty cool" a few days ago, so I'm in a much better headspace since when I posted the first time, and have liked all the other content I've posted so far, so next step is use all that stuff to get hired~
Edit2: That last edit had nothing to do with credibility or anything. I'm just super excited still. Whole "Senpai noticed me" thing.
Edit3: My 11 year old sister's got it down. Not that it means much since she's taking high school classes, and will be taking some college ones next year...but still, she went in with next to no experience in Pathfinder, barely picked up even just her class features (druid). Once we switched over, she had everything down the first game.