My bantam cochins (i now have some standard cochins) were good enough fliers to easily get up on the three foot perches. So, ramps would be no problem.
They are super cute and very sweet.
Remember that with those fuzzy feet, it would be best if you can figure out a way to give them a dry or at least not a super muddy run.
Only other tip.... Is I know I had a bit of a panic the time i saw blood all over one foot. With the feathered feet, it is easy for the feathers to get broken off, especially when they are growing in. If the feather is actively bleeding, you need to pull out the entire feather.
I only experienced a bloody foot once, and the feather had already stopped bleeding when I saw it, so I didn't have to do anything. But I have white cochins, so even just a little blood looks like a terribly large amount.
Good luck!
What colors will you go with, there are so many great ones!