I can't speak to the idea of smaller districts producing a more docile body- I think kids are kids no matter where you go. I taught 8th grade Social Studies at an underserved school in Houston. It was the middle school I attended growing up, actually. It was a familiar setting for me and helped me have access to many students that would probably never listen to other teachers. I knew the culture and what those kids faced since I came from a similar socio-economic background. You may find teaching a little easier if you land in a district that you're familiar with- one that will be easier to connect with the students. My relationships with the students was arguably my greatest asset and certainly helped with classroom management as well as helped talk kids down from those perennial emotional ledges.
Here's some of the issues I have encountered. Administrators will more than likely be the biggest thorn in your side. That's going to be as a result of several things- including just plan 'ole petty politics. Because of the lack of promotional options in education many (not all, but many) administrators will become school leaders not out of any dream of changing the contours of public education but out of a mere desire for upward mobility and characterized by a bigger salary. Their job isn't easy I'm sure but the vertical business model dictates that poop flows downhill and ultimately lands on teachers. Every administrator needs at least a few scapegoats to point at for the schools poor performance so learn to play the game.
Another issue that you'll encounter is state testing. Imagine that vertical business model where state legislators are at the top calling the shots using "end of year exams" as a method of "reforming" public education. With state funding linked directly to the testing results you won't be able to avoid the pressure. One thing you can do is teach a grade that isn't tested (like 7th grade Texas History). They'll probably still coach you into teaching in a way that prepares the students for the next years' test rather than the suggested curriculum model. When I was interviewed for my position the administrator said, "we don't want you to teach towards the test" which teaching to the test was truly my only option. Everything rises and falls on those test scores.
Expect a high turnover in your school. Nothing seems to be done at any level to keep good, qualified teachers from leaving by their 3rd year. The salary for Texas teachers is below the national average- add our low student performance levels coupled with new rigorous testing standards and it becomes enough to send many educators looking for the exit from the classroom. If you look at the trends from the last 10 years you'll notice some fluctuation in the retention rates, which coincides with the national economy. Too many teachers find employment with less stress and more money when our economy is on the warmer side.
Not everyone will share my views and some will have a life of substantial returns in education. I have a few friends that are hugely successful in the classroom and have managed to change the lives of many students. The rewards seeing a life change is moving to say the least. But the fact remains, if public education doesn't make some significant changes then the doors of our schools will continue to be revolving doors.