Well, as a (relatively) experienced but not pro player on Smogon, here's the problems I see:
-In traditional Smogon (OC legal) formats, the village is no longer an uninformed majority. This is because anyone who can clean themselves can then demand claims from every player in the game, and then use other players' actions to confirm or deny claims. That may sound obvious and basic to the experienced players here, but it's the root of all the problems with the OC format. When the village leader has all the information, then the BG always knows who to protect with 100% accuracy, the Doctor is always inspecting the players most likely to be scum instead of players they personally think are scum, and in the absence of miller/redirection mechanics it is EXTREMELY DIFFICULT for a united village to mislynch. This means that the success of the mafia factions is based on whether they can kill the two most important power roles (the BG and the Inspector) early on in the game. If they can, then they will probably win. If not, then the Village can simply appoint a leader and coast to victory.
-In traditional Smogon format games with anti-village leader mechanics, villager motivation quickly vanishes. Without information, most villager actions are useless or even harmful. Therefore, when the village leader is either inept or nonexistent, the village quickly becomes apathetic and gives up, with cries of "lol this game". This was most visible in Daenym's game from a few years ago, Turnip Mafia, where the game consisted of 14 villagers vs. a killing/recruiting wolf and his partner who had a single lynch redirect for himself and an infinite lynch redirect if anyone other then him was being lynched. After the third lynch attempt on the wolf, nobody was really trying anymore; everyone had already declared defeat. Now, that may be a obscure, absurd example, but we've even seen this happen in more recent games, most notably in the most recent Big game where once the villagers figured out that they were just pawns in the struggle between Dracula and Van Helsing and that they literally couldn't do anything on their own, they just quit and refused to play on, leading to the game's abandonment.
-In multifaction games, kingmakers are detrimental to the fun of the game. Allowing a faction that has already effectively lost to decide the winner is pretty horrible game design, but there's not much you can really do about it in multifaction apart from outright removing factions who could create kingmakers. However, multifaction with all factions somewhat informed is a pretty fun game until you get to the kingmaker, so there's that.
-In NOC formats, there's only so much innovation that can happen, but the same amount of mundane clerical work still exists for the host. This is because NOC formats, thanks to sites like Mafiascum and EpicMafia, have largely already been solved for smaller formats, with clear winning strategies available and documented for both the village and the mafia. Even with balanced numbers, slight changes in roles or mechanics like in my Twilight Princess mafia a few months back significantly changed the balance of the game (although the fact that it was a beginner and some of the village roles were never even used probably also contributed). The best balanced games in recent memory were probably Blue_Tornado's NOC games (Company Mafia and Mafia from the Depths), and these were considered to be well balanced, enjoyable games by the playerbase, although both were completely standard (with MftD even being an all vanilla game!). As a result, NOC games are fun for players, but limit the amount of fun available for the hosts, which is probably why we saw a move back to regular Smogon format after the last few NOC games.
After considering all of the above, I think that there are simply too many unresolvable problems with the OC legal format. Therefore, I propose that we mostly do away with the outside communication legal mafia format. NOC games have proven to be much more fun and (usually) more balanced, and series of random minigames like Bass' A Cereal Murder or askaninjask's ongoing Everyone Who Signs Up Will Be In This Game should also continue to be a thing on Circus Maximus. In order to fill the niche of "Outside Communication semi-mafia game", I suggest we move to tactical games like MGS mafia and the fairly recent Game of Thrones game. These have proven to be much more engaging for all players in the game then the village leader system.
tl;dr kill the smogon format and replace it with:
-more NOC
-more tactical games (where every faction is informed)
-more random minigame collections