The League system was made to make folks feel better about the grind of climbing. Hidding MMR gains and losses makes each individual match less impactful because a high # of folks will be like. Meh what ever im still in -insert rank-
MMR systems are percentile biased more or less. For it to function well it needs to track each player individually. For it to be Percentiles the starting point, the base MMR of any new account, can not be the bottom of the ladder. It tends to be roughly the mark for 50% of the player base above and below it. There is some discrepancy's off soft resets between seasons (that's a good thing for everybody thou.) As well as the impact inactive accounts make.
When your using MMR you inherently assume the system is wrong on players, its designed to be self correcting. This is one of the reasons you NEVER RUN STATIC ADJUSTMETS! You delay new accounts from reaching a realistic MMR. Some one so bad they always cripple their team will be in the standard MMR for a much higher # of games. In Elo this uncertainty is called K factor. Its used in the adjustment after games to control how fast new players climb or fall down the ladder. and its core to making a solid match maker. Do you want honest to god Diamond smurfs and the folks who truly belong in iron 4 to remain cluttering up the majority of your matches? You think that shits better for the quality of games?
Look. Its rough If your near the average level of skill. That's the most chaotic part of the ranked ladder. But its core to allowing bad players to sink and good ones to climb. it does not care about any one. just numbers.
Climbing is inherently harder then sinking. Basically Anyone can throw matches. Not everybody can carry weight consistently. Just the nature of the beast.
I made a pretty comprehensive FAQ on the topic once. Take a look at it if you want but please no necroing. I am happy to address questions here in this thread if you have any.
End of the day. Because of Adjustment formula being not static. In unfavored matches folks stand to gain more MMR on wins then they will from a loss. So you can honest to god climb the ranked ladder even with a 50% win rate assuming your on a unfavored team consistently.
You can make life better for average players by using a adjustment to your matchmaker to also try and priorities similar # of played games by each team, inside the acceptable range of MMR you give it to work with.
TLDR. Static gains are very very very VERY bad. Don't do it.