Better keycaps with better wear resistance
I suggest that Dell starts using 2-shot injection molded keys instead of the current pad printed keys, which offer several advantages. 2-shot injection molding (also known as insert molding) is when a plastic part is molded with multiple colors of plastic.
For reference, please read the "key labeling" techniques here:
Why 2-shot injection molding?
1. Extremely high contrast. 2-shot injection allows for extremely high contrast keycaps with crisp edges and high readability. The appearance would be significantly better than the current pad printed keycaps on most of the Dell keyboards.
This is a 2-shot molded keycap next to a laser printed keycap (which is what HP and others usually use on their desktop keyboards)
2. Wear resistance. Since the lettering is molded into the plastic and is not printed onto the surface of the keycap, it's practically impossible to wear the lettering off. This would address the issues of people wearing off lettering.
Note how the letters are molded into the plastic. This is impossible to wear off in practical circumstances.
(also notice the very high contrast)
3. Elimination of the printing step in keyboard manufacturing. Since the lettering is formed at the molding stage, the printing step in keyboard manufacturing is eliminated.
The issue with 2-shot injection molding is that the tooling is expensive than standard single shot injection molding. However, Dell produces/subcontracts keyboards at high enough volumes that the additional tooling costs would be negligible, and might pay for itself thanks to advantage #3.
Also, if possible, make the spacebars out of PBT plastic. PBT is harder than ABS or polystyrene usually used on keycaps and significantly more resistant to shine and wear, but it's pretty much impossible to 2-shot injection mold. Still, there's one place where it comes in handy - the spacebar. No printing goes on the spacebar and it's the key that receives the most use and is the first one to get shiny. (My Latitude E6410's spacebar started to shine only after 3 months)
(photo credits thanks to Ripster, a member of the Geekhack forums)