Knowing to push for level 2 when you have an agressive ADC like Draven or Lucian is a good start.
Just one thing to keep in mind is you should probably still go hard for level 2 even if you don't have an ADC like Draven or Lucian (if the matchup allows you to).
It's ESPECIALLY important on champions like Thresh and Alistar who's weakest point in the lane is usually level 1.
It's good to go into lane with a 'game plan' and it seems you're doing a pretty good job of that by deciding beforehand if you are going to aggressively pressure level 2 or play safe if you have the potential to lose hard level 1.
Laning is super important, especially since the game is so early game focused right now, if you roll over your lane you have the potential to pretty much remove the enemy ADC from the game.
(and yes, vision is SO POWERFUL. A lot of people underestimate just how useful it is to know the location of certain enemy champions.)
Fighting around cooldowns is super simple and easy to do, a lot of people just don't think about it.
Just think about important abilities, take for example Morgana Q.
If Morgana misses Q pre-6 all she offers to a fight is her pool and spell shield.
In short she pretty much loses all pressure that the ability creates.
So while it's on cooldown you can either harass her and her ADC for poke or try to pick a fight knowing she can't root you.
Same thing goes for other abilities like Blitz/Thresh Q, or Ezreal E.
If a champion doesn't have their primary CC/engage/escape available it usually sets you up for a good opportunity to trade or fight.
Same thing goes for your side of the lane though, for example if you're playing Thresh and miss a hook (it happens to the best of us, nobody is perfect) you have to realize that you aren't nearly as scary until that ability comes back up.
