Here's a slight tweak to the original route:
If you want to avoid two sorta-steep hills (the one between 20th and 30th on Harrison and the one going over the south side of Tabor), instead of turning onto Harrison of Ladd's Circle, continue down SE Ladd Ave to the 20th/Division intersection. Quick left on Division, then quick right on 21st. Left on Clinton (at the blinking red light) and continue until you hit 51st. Right on 51st, left on Woodward and continue until you hit 75th. Left on 75th back to Division, quick right and then quick left again onto 76th. Then right on Stephens and follow the rest of the route posted above.
It adds more distance onto the route, but you do avoid two good sized hills. You still have a gradual climb on Clinton from 20th to about 28th, and 51st between Clinton and Woodward is a short steep hill. But it's another option.
See the map here: