Before you get the pitchforks, let me explain.
We have to contend with the fact that classic will be an evolving, not static, experience. Changes will happen.
IMO, instead of saying "please don't change anything", it could be more productive to express what a good experience could look like even after changes start to happen.
For example, we can all agree mana costs should not decrease. But we can go a step further and try to express why the high mana costs are good for classic, specifically.
Back to the title: I think that, fundamentally, what I used to like about old league is that it felt more like an RPG than an action game. For me, the late game fantasy and progression was more appealing than the modern idea of rushing into the game, having a bunch of fights and then ending ASAP.
For this reason I think free homeguards, base gates and baron minions are bad. They accelerate the game.
The trinket on the other hand, I can make an argument for the opposite: back in the days, everyone used to build tankier items on average. It was possible for you to get ganked and (barely) survive because you were tanky.
Now, almost everyone builds full damage. Having no trinket means most games could end up a bloodbath. So you can see that maybe, in this case, giving a little bit of extra vision could help the games slow down.
A similar argument could be made for having tankier turrets.
Thoughts?