Has there been any consideration to changing the early game power level of turrets?
I agree that they should be a place of sanctuary early, diving should be strongly deterred. Yet I find their power isn't like this at all.
Even pre-6, supports will tank the turret in 2v1 dives bot Lane. Often someone will tank a couple hits during a jungle gank. Successfully taking anything more than 1 turret shot during a dive pre-6 should be reserved for the very few champs that have something in their kit to encourage diving...
On the other hand, I find trying to take that first turret to be very frustrating. I can be winning Lane pretty consistently where my opponent refuses to feed me and just bases repeatedly early game. So I push the lane in and do some turret damage each time, yet it never seems to add up. Eventually their turret is at half health and mine's not yet touched and I get ganked and escape to recall and my turret is destroyed before I get back. They've recalled under pressure 5 times and I've only got theirs to half health, the first time i recall without pushing out the wave first I lose the whole thing. It happens because there seems to be this point where champions suddenly start to deal a lot more damage to turrets and the enemy has their jungler helping to take it down.
What I want is:
Early game turrets to be more threatening when a champion is there. Dives should be strongly discouraged unless the enemy is nearly dead and you're nearly full.
Early game turrets to be easier to take. Reward people who win push out a safe opponent who refuses to give up kills (specifically weak roamers who can't get kills elsewhere).
I'd suggest making a change to Tier 1 turrets:
1 - increased damage to champions when an allied champion is under the turret. If an allied champion moves within the turret range, the turret gains 10% bonus damage to champions per second stacking up to 5 seconds (the bonus could be altered). This makes chasing someone into their turret unchanged, but makes diving someone more risky once they've safely been at their turret for a while (i.e. you're waiting for your jungler to come tank it).
2 - bonus damage against turrets. If no allied champion is within a larger range of a Tier 1 turret, the first champion to attack the turret receives a buff that increases their damage against turrets for a few seconds. Either on-hit, or attack speed boost, or otherwise.
I think this would transform turrets in to what they spoils be early game. Places of safety for a defender, but a key objective to take when your enemy surrenders map pressure. Not everyone can roam or take Dragon whenever they push the enemy out of lane.