I think honestly you can't force, nor you can expect people to play at the same level as pro players just so that they can avoid snowball. The first reason, and the most obvious, is because people have different skill levels and not all people are going to be able to play at that level; either because they just don't learn, or have no interest or time to do that.
The second reason is that it is less fun this way. I am not a pro player myself, but I am pretty sure that the current state of pro games isn't boring just for who are watching. I am pretty sure that pro players also find those games to be boring (even if you play something to win, that doesn't mean you can't have fun playing). If you aren't having fun, what is the point to play? It is not fun being stomped, but it is also not fun either to be forced into long, tedious games with no action until a late game teamfight happens.
The third reason is that a big part to why pro games are not snowbally is because of items and runes, that should be properly nerfed. I think champions kit also has to do with that. For example, as long as assassins have delayed burst and shielding is omnipresent, we will never see assassins being a viable choice outside of SoloQ. And as long as pro players can just funnel gold into one or two teammates and rely on them to carry, there will be no reason to not pick a tank in the jungle and in top lane.
I think this is one of the few things that should actually be balanced around low elo, but of course, without disregarding competitive games. This is because what's the point of having a game that is fun to watch, if the meta is different in competitive, and due to that you can't have fun by playing the game itself?
Also, if towers were stronger, I don't exactly know what would happen. With "strong" do you mean towers being more durable, or dealing more damage, or both? Because the first would mean champions with strong anti-tower capabilities would become meta. I predict Ziggs becoming meta if this happened, since he is a dedicated tower buster and waveclear champion (he isn't meta right now because there is no need to have a dedicated tower burster when you can already destroy towers with other champions that have other tools or are just more versatile in general). Champions like Jinx, Yorick, Fiora, and Trundle would also be strong choices, and Tristana would be even stronger than she already is. In the second situation, I just predict the meta being the same as now; because dives are discouraged, early game aggression isn't as strong, so matches are stalled. Regardless of what would happen, I think the game could become slower paced, although if mistakes were punished less hard and scaling champions took more time to scale, we could still see early game or playmaking champions like Lee Sin being played. In the end I am not sure about what would happen.