I was bored at work so I drew up what I thought MM should be and I'd like to explain some things.
Firstly the left side could be considered the competitive side and the right side could be considered the casual side.
I'll start at the top and work my way down to the bottom.
Team Arena would remain the most competitive playlist this would be the playlist to get ranked in. It would remain Slayer and Objective. It would remain pretty much exactly as it is now but this would be the one playlist that is BR/AR starts.
Moving down we have Slayer playlist and this would remain completely unchanged from what it is now this would be AR/Pistols feature all maps it currently does and be for 1 to 4 player fireteams.
Now if you look to the right you would see the mercenaries playlist Lone Wolves. This would be an unranked exact mirror image of Slayer playlist. You could only enter Solo but it will team you with 3 other people and face you against another team of 4 Solo players. My thought process behind this was theres really two options that can happen.
1. A offshoot of Team Arena or Team Slayer that is unranked.
2. Stricter Fireteam priority matching is patched into the current playlists.
The reason I went with an offshoot is because I think the second option above could ultimately lead to longer mm times and some people not being able to get matches. If you are searching as a team of 4 in a playlist and it heavily prioritized getting another team of 4, and then secondly its trying to match your ranks closely, all on top of the most basic neccessary priority, which is being able to actually network to each other and have a quality mm experience in terms of latency, that suddenly becomes quite a lot of filters that might narrow and narrow down the player pool to something undesirable, and possibly that could be taken advantage of. Another important reason though is because solo players need a safe place to go where they dont have to either play FFA or face teams. The reason I went with Solo only is because Teams can easily go into this playlist that's unranked and shit all over kids that are learning the game or trying to have fun and aren't competitive players. Making it Solo queue Team playlist offshot is the best option I believe. This is going to lead players into a playlist when they are solo that seems like from the initial start the game will be fair. You can even rank this playlist but have it hidden to create even more fair matches.
On top of all this the playlists MM is already pretty good most people agree this game produces the most close matches more so than any other Halo game.
Moving on Doubles needs to be a playlist not only is this a Halo staple from every past Halo game and should have been a playlist at release. It gives players who's full teams haven't come on yet something to do other than wait. There are also a ton of duo's that just love doubles and play it nonstop. This gives groups of 2 something to do.
Now that Solo and fireteams of 2 have something to do. Lets move on.
BTB of course is going social. Its crazy chaotic and fun. It shouldn't be ranked though. This mode is about kicking back and watching antics ensue. Not getting competitive. Sorry Gamesager. Also a star is on BTB cause this is the only playlist that will feature JIP. Another reason why its unranked.
Breakout will remain untouched. However, it should be removed from Arena.
SWAT is pretty much the same however I want all the precision weapons to really get a chance, I think SWATnums is OK, but you should be able to see some matches of Carbines, Light Rifles. Battle Rifles, and DMRs.
FFA will remain untouched, 6 player FFA games Pistol/AR starts.
Over on the bottom of the casual side you have the weekend playlist. However once the weekend is over Action Sack should be switched in the weekend playlists place. Once it becomes the weekend Action Sack should be swapped out for the Weekend Playlist. This helps the playlist number stay low but always keep a weirder Halo variant available to the community.
Weekend Playlists won't change much but when Action Sack comes around during the week it will include most Weekend Playlist past variants and it will also include Fiesta games as well as the Armory. The armory is basically games with one set weapon. So you can get practice with each weapon and get practice beating enemies that have the same weapon as you. So for instance you will play a game of Swords on Eden or Light Rifles on Plaza or Needlers on Regret. No weapons will be on the maps and you have to outplay your opponent who have the same weapon as you.
That's about all I have for now.