Braes Bayou is a concrete lined bayou. The secret is to stay on the north side once you are west of Buffalo Speedway. It is almost exactly one mile between Buffalo and Stella Link. Cross Stella Link and stay on the north side to the railroad trestle. Walk beneath the trestle, over one of the feeders and you will be between the water treatment plant (I know, whoopee, but it is Houston, what can you do) and the bayou. The north side is more quiet and beneath the trestle you may be treated to close up views of egrets and herons (I know, whoopee but make the best of it) or my dog chasing egrets and herons.
Braes bayou is a great place for a long trek - walk, run, bike, whatever you're in to. Yes, there's a lot of cement, but in you're in the middle of a huge metropolis and this is not a park. (Get over it!) There is wildlife: fish jump out of the water, birds fly, dragonflies hover - again, you're in a city! Perhaps the best chance for a wildlife "experience" is to be on the bayou at dusk. You're likely to see many bats flying around for their dinner!
Concrete canyon. Yuck. Some birds/fish, but don't waste your time. Only attraction is proximity. If you want a quick one'ish hour activity, close to where you are, this would work. But don't get your hopes up regarding fun, wildlife or scenery, unless you like seeing urban sprawl.