Rationalizing U.S. Currency for the 21st Century

U.S. cash currency has a couple problems that should be easy to solve:

1. Inflation has eroded the dollar's value, so the lowest denominations are less useful.

2. There are too many paper notes and not enough coins. Paper notes are more expensive to produce and to maintain, and coins are more useful for vending machines.

3. America's rich diversity is poorly represented.

One online campaign is pushing for Harriet Tubman to replace Andrew Jackson on the $20 bill. That'd be a good switch, though I have an even better idea. Here are the changes I'd make simultaneously:

A. Stop producing pennies. That takes Lincoln out of coin circulation, but he's still safe and secure on the $5 bill.

B. Stop producing $1 bills. That takes Washington out of bill circulation, but he's still safe and secure on the quarter.

C. Ramp up production of Kennedy half dollar and Sacajawea dollar coins.

D. Put Harriet Tubman on the $2 bill and ramp up its production. That takes Jefferson out of bill circulation, but he's still safe and secure (for a while) on the nickel.

E. Switch all paper currency to more colorful, Singapore-style polymer-based notes.

It'd be nice to stop producing the nickel, but either the quarter would have to be demoted to 20 cents or it would have to be yanked as well. And these are the coins with Jefferson and Washington. If any old white men belong on U.S. currency then they do. If you really want to pull the nickel then here's one way:

AA. Stop producing pennies, nickels, quarters, $1, and $2 bills.

BB. Introduce a new $2 Jefferson coin in a substantially different form factor.

CC. Ramp up production of the $1 Washington dollar coin, already produced as part of the presidential series, but with Sacajawea on the obverse. (Or put Washington on a new 20 cent coin, but that's a bit confusing.)

DD. Introduce a new $200 Harriet Tubman bill, probably (unfortunately) with a limited but regular production schedule.