I'm not exactly downtown; I'm 30 miles away, halfway between Houston and Galveston. I usually fly fish from the shore or my kayak in the gulf. Not too much fresh water around here, but lots of salt.
I use an 8-wt since there's usually a lot of casting into the wind.
Plenty of bay fishing spots. If you are not up for the drive, or want to stay in fresh water, I know of a couple on the west or southwest side about 20 minutes from downtown to just get a line wet, freshwater. But it beats watching tv all night. Let me know and I can give you spots.
Yea its right on the beach so drive up, dump off, and go fishing. Ideal for kayaks because there are usually no waves unless the wind is blowing hard onshore from the easties. Kayaks also protect you from rays that love the flats.