Substitutions: The only upgrade I want to see from Rito

Disclaimers:

1. I'm a filthy casual. I admit it, but I don't have the time to dedicate to Competitive. I have a wife, a job, and other things that demand my attention.
2. I also do NOT like the way Riot has the competitive algorithms working. If you queue up at the wrong time of day to play your provisionals, you're instantly stuck in Bronze/Silver. Therefore, I won't play Competitive any longer, nor is this post about Competitive.
3. I'm talking ONLY about casual modes; ARAM, Dominion, casual SR.

All I'm asking for is the ability for AFKs/trolls to be substituted (maybe kicked, if this plays well).

A. There is no reason a MOBA can't have substitutions. I use FPS games like COD and CS:GO as an example, but their casual modes ALL have substitution. Someone quits or afks? Meh, kick the crap down the road and let someone else join. The attitudes of the people who play casual MOBAs and casual FPSs are shockingly similar, in my experience.

B. But the characters! The characters and the skills and the items! Alright, fresh layer of hell for the devs to figure out, but even then it's not so bad. Someone AFKs from an ARAM, and even a troll leaving a poorly built character behind is better than a simple stompfest 4(or 3 or 2 or 1) v5.

Rito has a lot to work around mechanistically, but these should be the GOALS:

Ultimate Goal: Anyone can join with any character (per each maps' rules), runes, masteries. In an example like ARAM, the auto-leveling already works well, so there isn't much concern there. Items and gold are reset so no one has to figure out "Hey, how will I deal with this AP Tank ASHE with 3 Catalysts of the Protector?". In SR, they might need to accelerate the leveling algorithm (i.e. If everyone is already 10, you join at 5 and scale faster; everyone is 15, you join at 12, still scale faster; etc.) but items and gold are reset and you can still play any character/rune/masteries.

Intermediate Goal: If I understand correctly, Rito makes each game lobby by loading characters/runes/masteries, and then you have to itemize and kill your way to the finish. Fine, let me join as that crappy AP Ashe, but reset my items and gold so I can make the best of it. Playing 4.8vs5 is still a better ARAM/SR than 4v5 (soon to 3v5 when someone else decides to quit).

Shorterm goal: Test this whole thing out in a new game mode. Heck, recycle code from a Dominion game or something else, but figure out how to make the game more modular there.

User Settings: Okay, so you never want to be the pinch-hitter for a team? Fine, but I do, because I play FILL on every game anyways. This is a serious non-issue for me and my approach to the game. It's about the TEAM, not me. But hey, everyone plays the game differently, so Rito enables a setting in my Summoner's Profile where I can elect to be a "fill-in" player in casual game modes. If not, NBD.

I get into game quicker, and my brain is challenged in a way that no other game is currently doing, "You're dropped into the middle of a conflict that has already developed organically, and you have to make the best of it as a probable underdog - GO."