I agree that AFK-ers in ranked need harsh punishments. However, I have brought this issue up before (years ago) and I've had a lot of time to think about it.
The Problem is Logistics:
How do you determine who needs harsh punishments vs who should just get a regular loss? About 5-6 years ago, I had one instance that I lost a regular game because a storm knocked out my power and internet for days and when I got it back, I had a temp ban for league because I had left a regular in a recent game and when I disputed it, they never said it was for repeated offenses. The response was "don't play when your internet is unstable," and I think that was because there was no history to actually point to.
The problem is, how do you tell the difference between intentional AFK and Janna throwing her Q at the power lines outside your house.
The time investment to investigate and appropriately dish out ranked punishments vs reward to Riot community is actually minimal.
Although the benefit is great, the time and effort investment is even larger than the benefit and so it's not worth it for Riot to actually do it.
A potential solution: Try queuing with friends
I know it's not solving the problem as a whole, but it helps solve your individual experience. Get some friends together and play together. I know it's sometimes hard to coordinate and what not but it is possible. I know people can be very competitive with League and I go to Pax and I watch the games and cheer with everyone in the crowd too. So I completely understand where the competitive feel comes from.
I wish I had a better solution to give you but at the moment I don't have one.
If I think of something I'll definitely post it on the boards.
