Here’s what is important in my opinion…
It is good design, for a sleeve-type bearing setup, for the bearing to be softer than the slide/rail/shaft. This way, the bearing wears out before the shaft. This would be the case for either of your options, but I presume option number two would lend itself to a quick swap of a sleeve should the bearing wear out. So, I think option #2 is good.
Also, as for material, aluminum isn’t necessarily bad if it is appropriately sized for the intended use. You do not want to run ball bearings against aluminum, no, but for a sleeve type bearing application, plated aluminum is fine. Chrome is good, anodize would also be good. The plating protects against oxidization and provides a hard surface to resist abrasive wear.
Hopefully this helps you with your project.