Considering that your tank is 30 gal, and you don't expect to be installing a skimmer or refugium, and you plan to do weekly water changes to maintain the water quality, I have to say that I think getting a controller would be a waste of money, and not at all cost effective. Lighting can be controlled with a couple of timers, and the you can add the test kits, thermometer, and a refractometer for a lot less than the cost of the controller. I recommend that you save your money at this point. Controllers are still on the somewhat expensive side, and while fun to play with, are not going to add too much to the type of system your planning. Outside of lighting, and maybe an auto top off, you really don't have much to control.
To put it another way, you have a comparatively low tech system, which will work fine, just as it is. Adding a controller to such a system is sort of like going out and buying the lowest price new car you can find, and then putting $150,000 in to it for custom body work. Or as another guy put it "Don't be too proud of this technological terror you've constructed. The ability to destroy a planet is insignificant next to the power of the Force." (grin)
If you had a much larger tank, and a lot more to control, then a controller could be a very good addition.