Far western KC is still being developed, and there are a lot of great areas with new, wide roads and little traffic (Western Shawnee, Lenexa, etc.) Avoid De Soto since they don't allow riding within city boundaries.
Just areas that are condusive to good road biking- wide roads, scenery, supportive community(events), bike shops etc. etc. I was just trying to get a read on what people thought was "good"in their minds!
I live in Clay County, just Northeast of Liberty, and we have some great roads out here for cycling. Very little traffic, rolling hills with flats and descent climbing, with the country scenery. Nothing like riding through the rolling hills with open fields surrounding you with the a beautiful sunset.
Let me know if you have anymore questions. I posted some of our weekly rides on mapmyride.com, with the starting location of Excelsior Springs, MO.
Yes, you will be right near cycle city in Liberty. They have group rides on Wed. nights and Sat. mornings. I've never ridden with them as I live a little north east of there, but they are cool guys. I'm sure they can point you in the right direction for best routes in the area. When I ride into liberty, it's usually on the south side coming up Hwy 291 or H Hwy on the north east side. Either way, you will have some good country roads to explore, or city roads if that is your preference.