I don't think you can improve on the combo of: 1) slider/knob 2) text input

What you can do depends on if the range is known, and what precision you want: • Less/More: for steppers with < ~15ish value • Min/max: for defined ranges where the user wants short bursts • Accelerating hold: when the user wants precision in the beginning but the range is wide so holding is a good indicator they wanna go farther raster. • Copy from or value suggestion: when the user wants this value to match another (maybe something recent) • Speedometer/pie: when the range is well known and there's some tradeoff to another value (ex: two values are constrained to equal 1). Often mixed with locking if > 2 values are part of the constraint. So lots of ways, have fun!

Wow, great list @Don Abrams!