Unhealthy gameplay mechanics

I was watching LCS CG vs 100 thieves game 5. Both teams did really great and congratulations to them both. Late game ending still seems to be a problem and some items are unhealthy.

1. Elder dragon is essentially trash compared to the Baron. I think you will need to adjust Elder to make it comparably as good.

2. Warmogs is way too OP. If all teams realized how strong Warmogs is then you would have 3 tank comps every game. Warmogs essentially negates any late game damage to the front line. In a 3 tank comp, the tanks can safely rotate to the front line each taking turns healing back up using Warmogs. This is unhealthy for the game.

3. Banner is unhealthy for the game. In late game matches where priority is put on Baron power to win, there is no reason that a bannered up minion should win the game for a team. Not saying it happened in this game but in theory it could happen. The banner just delays the real action of team fighting by forcing players to address the minion or lose the game. This feels real dirty especially when the teams invested so much strategy, time and effort into making it a late game anyway.

Unrelated issue:

All champions have abilities that they can use to clear waves but only AD champions buy AD items which help them clear waves by just using auto attacks. Additionally both AD and Tanks have access to good items to help them clear waves ie static shiv and sunfire cape. The mage class is at a handicap in clearing waves. They do not buy those items nor do they buy AD items to help them clear waves. This seems a bit unfair in the sense that they are expected to use their abilities to clear waves. So now instead of having my abilites and mana available for fights I have to use it to clear waves whereas an ADC can auto the waves and keep their abilities and mana at the ready. Both are equally as squishy so I'm not sure why the mage class is handicapped versus basically every other class in the game.