On a big quilt I use 2 1/2 in strips. and do the sub cuts starting at 3 1/2 then 3 and keep decreasing the size until I get the 1 in.
When you want to make a very steep valley with the colors you could go with the 1 in pieces three time, then start moving the color up with a coupl1 one inch cuts, then start adding 1/2 to each of the cuts.
Draw it out on paper...you don't have to color all the litted spaces, you can see a pattern forming. Just work on the design on paper until you get a pleasing look.