I don't own a Harmony, so what i will say might not be relevant, but if in the future they might think of a small change (to make it more useful for button pushers) here is the idea I got

why not change the way the LCD works. From what I understand there is a wheel that you turn to go up and down the choices, you stop on a choice and click to pick it (I would guess a bit like a Blackberry). Here is my idea
use a 6 row LCD with on either side push buttons (a bit like the MX-500. and on to p and button of the screen one more button.

you add a total of twelve buttons, and you can get rid of the wheel. The two buttons would work as a scroll up and down of pages , the other PBs as choice selectors.

Why 6 rows
1) 12 is easily divisible (2,3,4,6,12) - yes buttons will not be used, but they can mimic themselvs (and you will have the possibility of bigger writting
2) 12= 10 for keypad plus two for possibly enter and 100 that is needed on some TVs
3) For the TV listings the two columns of buttons could be used for different things (Main TV, PIP, Record....)

This is just an idea I had on the bus this morning.