Inter-champ synergy, you're thoughts

Just a few things I'd like to know about synergy between different champs.

• He's the most apparent. His ult relies on landing a knockup. While he can do it himself, it's much more effective (and fun) if you have a team full of them so you have more reliability and can come from farther and more varied angles.

• Not as well know but her Twin Fang can reset on multiple poisons and not just her own. With the exception of Twitch, since you can't amp true damage, she will also buff the poisons of the others.

First question: Do you like having abilities on separate champs that work together?

• Anivia's Frostbite deals double damage if it hits a Chilled target. Sejuani's Permafrost can only hit enemies with Frost. The idea is their abilities are affected by the cold. There are many other champs that have cold effects like this. The thing is, none of these effects work with Anivia or Sej's. What if they did? Would that make them more viable or even too strong?

• Now imagine there was a champ that had an effect with water. Say he moved faster or could sink in like This would probably be useful in the river or with his own abilities that create a temporary pool. What if and could help? Chum the Waters could leave a trail from whoever it hits like Duskbringer. Tidal Wave could have a giant stream in its wake and Riptide could soak a wide area.

So the second question: If a champ has the potential for great synergies, should older abilities be changed to accommodate it? As long as it doesn't change them too much, of course.

Finally, can you think of any cool synergies that you'd like to see? If you'd like to see them at all?