Well, you said it.
1- For starter adding custom keyboards to commands so it could present possible answers for that specific command.
2- Also right now keyboards just repeats whatever option is selected (if im not mistaken), while you can create custom keyboards using telegram api to do more. For example if you select “Yes”, the bot gets the message to run command 3 which also have its own “Yes” option which will run command 5. I can imagine this kind of flexibility would make things complicated on your side.
3- And for design, buttons can have custom icons and colors but IDK more about that. Having more options to custom create keyboards would be nice.
I think its safe to say telegram will continue to push the boundaries of its bot platform (new inline bots for the latest update) for a long time. And as a fan of your plugin I want you to know I understand its not possible to develop a wordpress plugin to do as much, toe to toe.
So thanks for your good work and keep it up.
I wish I could do more.