Fraxinus Excelsior pollarded bonsai?

New in my collection of raw material, since early april this year. This is Fraxinus Excelsior, the common European Ash.

Hasn't really recovered fully from collection this year, growth was quite poor but it survived well.
Let's see what next spring brings, I'm hopeful!
The idea is to create the image of a pollarded tree, which is quite typical of the region I live in, with Fraxinus Excelsior being one of the typical species uses for that.

I'm aiming for a 5 year plan before it'll start to look decent and be able to put in a good pot. In 10 years I should be able to have a canopy that only needs maintenance.