ITT: Ideas to make trading more attractive again and the central part of the game again.

I think something like Vivillion should exist for more Pokemon than only Vivillion. That was a really cool idea.
Make Pokemon have different sizes and make it visible on the model.
Have prominent features of Pokemon be different. Like if a Pokemon has a pattern, randomize it like with Pandir.
Have Heracross' horn have different sizes, etc.
Just make the Pokemon feel more individual