[Barnsnake]

With 1.25" cylinders I'm sure your required pedal pressure is REALLY high.

Assuming your pedals have the same lever ratio that I'm familiar with:
Many people with that brake combo use a 7/8" rear and a 3/4" front. It's a reasonable compromise of effort versus travel. Another approach is a 3/4" rear and a 5/8" front. Lots of braking power, but considerable pedal travel. The .700" front makes a good compromise between the two.

See what the brake manufacturer's on-line calculators say. In my experience they tend to lean toward the high-effort, short-travel setups.

Don't forget that the coefficient of friction of your pads will also change the pedal effort with the same mechanical advantage.

If you've been driving it with 1.25" cylinders, you'll be thrilled with any of the smaller options.