I've started doing the Ann & Roy Butler hike-n-bike trail on the south side of the lake, starting E of I-35 at the Roy G Guerrero Park. This has a couple of advantages:
(1) It's a heck of a lot less crowded than the main stretch of the trail, east of Mopac, with a somewhat more chill vibe.
(2) You get to walk on the lovely boardwalks that the city constructed over the lake.
You can get an ~4-mile walk between Guerrero Park and East Bouldin Creek, including some really nice lake and city views. Not a lot of shade, but for an after-work walk, that's not so important.