I know that it would be a bridge too far, but having worked at a business (movie theater) that had prices only ending in 0.25, 0.50, 0.75, or .00, I would love for the whole country to just have quarters and be done with it.

Though, since I rarely handle change at all — if I do use cash, I usually find the first place near my hand to donate whatever metal comes back to me - I suppose I’m not the target audience anyway.

Quarters are too ingrained into things to get rid of them. So many things take quarters. And your base unit coin needs to be divisible by the rest. So we can't get rid of the nickel without also eliminating the dime... because we aren't replacing quarters.

What about the 25 cent piece (the quarter)?

Did you ever noticed that gas is priced down to the mill even though those coins haven't circulated in a long time? Most people don't even know what they are.

I think it would be a fine to drop the penny and nickel from circulation, just let it become an obscure unit.

Change them to 20 cent, "fifths" :-)