I think it's time to diversify the towers again.
Tier 1 Should function similar to how they do now, but as they "ramp-up" they should get an all around increase, so fire rate, damage, and projectile speed. (this way the long draw out dives we see right now with tanky divers wouldn't be so much of an issue, while assassins would have a reason to exist.)
Tier 2 Towers should be rapid fire low damage projectiles that slow enemy champions hit. (the idea being you can make a stand at these turrets without just being poked out of the way when behind.)
Tier 3 towers would be extremely slow, but powerful shots with some splash damage around them. (they're slow so that you can break a line behind them, but they won't be pushed over too easy.)
Tier 4 in my ideal world would be laser turrets, but can attack multiple enemies. (this way there has to be an actual decisive battle to be able to push these over, not just a casual attack here and there.)
Add a Elemental dragon that creates a shield to allied champions occasionally, (like no less than once a minute,) when near towers, and I think the games would be much more interesting.
