There are trout from the beach front / jetty to the north end of the bay right now. When the breach fall below 75 to 70 they will start to make a hard push back into the bay. Honestly I would pick a area and just go brake it down. Move around looking for areas that have a lot of bait and fish them on different stages of the tides. It might not hold fish on a incoming or outgoing but will the other way around. This time of the year a out going tide is better normally for me, because it's pulling the shrimp out of the marshes and creeks into the bay. Rocks / rockwalls, oil rigs, reefs, shell, sand, mud, marshes, creeks are all holding trout right now. Its about as good as trout fishing gets and will only get better as the temp starts to fall as the fish move to the wintering haunts. I hate to say it but your going to be catching loads of gafftops they're chasing the same bait as trout this time of the year.
There's a lot of areas you can run your boat.. mostly Galveston Bay from the jetties up to Upper Galveston, East bay would also be a good area normally. Only really big shallow areas to watch out for there will be Hannahs Reef in east and Todd's Dump in Galveston near Redfish island. Use your Navionics or lowrance base map and it will help a little with general depth. You should be fine staying in areas that are at least 4' deep with that boat. Our Reef Recon will put the exact reef boundary on top of what ever base map you use. The Reefs on Reef Recon are layered into different categories such as 'Shallow Dangerous' and 'Caution' and 'Deep' (over 4' deep) to help you not only find fish but also reduce damage to your rig. It's the most recent oyter reef map of Galveston bay and the only one that puts the edge or boundary of the reefs and rocks on your GPS unit.
Someone recently said such and such base map is more precise and detailed that Reef Recon ... but it's truly not like that.. Reef Recon enhances all base maps with reefs that they don't have on them.. none of the base maps have deep oyster reef on them. Reef Recon has Shallow reefs, reefs just under the surface, all the way down to reefs in 10' of water and the only reef map where you can see the edges of those truly hidden reefs. I made it because we all needed it to protect our investments of our boats and help us catch fish. it was something I made for all of us.