I just wanted to say that it is really nice to see FaceIT making changes to the way queues work. There are and there will be people complaining about those changes e.g. the ones who cannot queue as a 4-man premade, but I would like to point out why overall it seems like a good change to me.
Setting a premium queue where you can solo queue or with a party with maximum 3 people in it reduces the risk of voting system getting abused. We all know the stories of 4-man premade kicking someone out of the MM game without a good reason, right?
Is there any other reason why limitting the number of people to 3 and not 4 seems to be reasonable?
Yes, I think so. Being a solo queuer and getting matched with 4-man premade as your teammates can be a great experience, but it can also be pretty awful if they use a 3rd party voice communication software which results in you not getting enough information or them not calling in-game at all. Not to mention, 4 people speaking the language you do not understand is not that much fun either. It does not guarantee a similar thing will not happen with 3-man premade, but I think it reduces the risk of it.
Besides that, it is simply easier to find one person to join your 4-man premade than it is to find 2,3 or 4 people and queue as a 5-man premade.
If you are a 4-man premade looking for the 5th, there are bunch of websites that you can use or even use the feature within FaceIT - https://www.faceit.com/en/csgo/teamfinder or https://beta.faceit.com/en/home/teams if you are using the beta site.
Last but not least, facing well coordinated 5-man premade when you are a solo queuer does not seem like a fair thing to me.
I hope the new system will improve the FaceIT experience for all of us. That is my two cents.