A few things:
Sliding the markers in and out might hurt the bottom of the markers? Maybe? - I'm not sure if you padded it somehow.
Also - I have been using this method for some time, and for anyone at home who owns multiple markers, but can't fill a cabinet, I used one of these "paper filers" to do exactly what you have.
I only have an ion and AMG laying around right now as I'm in my dorm.
Maybe you could install these directly in and save a little time?