"Blind, Drunk, Burning, Reach, Flanking.." Que the next rules thread debate. :-)
I've seen that Adv cancels Dis, but I have a 2d Adv type thing come up on Matt Mercer's game Critical Role. So even though it seems like it'll make things simpler (and it certainly does seem to do that in the 5E game engine) at higher levels it can still start to create almost an endless "do loop".
The way it worked was if you're blind, you have disadvantage on attack rolls; if you're drunk, you have disadvantage on all d20 rolls and 1d6 damage resistance whenever you took it; if you're on fire, you take 1d6 fire damage/round (possibly negated by the damage resistance for being drunk, and yes, that's how it worked in the playtests, and anyone who melee attacks you takes 1d6 fire damage; having a reach weapon gave you disadvantage on attack rolls against adjacent opponents; and flanking an opponent gave you advantage on the attack roll. So you ultimately roll 1d20 to attack.
Not surprisingly, this was dealt with in the next batch of playtests. (I think that was the playtest round that said "You know, rogues don't really need Sneak Attack..." The next round came four days later and was pretty much "We were wrong!" Then again, playtest Sneak Attack was extremely lethal.)