The current proposal for the latest widening of 518 is supposed to include a bike lane. It's getting lots of push back. Honestly, as someone who lives down here and does enjoy biking in the area, I think trying to put a bike lane on 518 would be a terrible idea. There are cutouts to shopping centers all along the way. It would be akin to putting a bike lane on Westheimer between 610 and the Beltway. I think they'd have a better chance with running bike lanes on Hughes Ranch to the north and Magnolia to the south and run N/S lanes along Cr 90, 94, 1128 and such to create connections to 518.
There is a recently added multi-use wide sidewalk along the newly widened Bailey Rd (CR 101). The Clear Creek trail project is supposed to be about 21 miles of multi use trail from Dixie Farm around to I think Almeda. There are parts of it in place, but that's a decade long project.