The reasons I think energy should be controlled at the federal level are:
1. It is a domestic security issue, perhaps the largest one out there.
2. There needs to be national standards for fuels, having 45 different blends of gasoline for 50 states is terribly inefficient.
3. The electricity grid is nationally and internationally connected. The outage in Ohio a few years back took out parts of Canada and NYC also.
4. The need for some sort of alternative energy is clear. I'd rather have us move forward as one country rather than 50 states moving in every which direction and some not moving at all.
5. In energy, buying in bulk matters.... a LOT.
The reasons I think transportation should be controlled at the federal level are:
1. CARB.... do I even need to remind anyone of this?
2. Most transportation is interstate.
3. There need to be national (if not international) standards for emissions, safety, and efficiency. Not just for cars, but for ships, planes, and trains too.
4. The Interstate highway network.
5. Air Traffic Control
I'd prefer that Social Security would be privatized, but I fully admit that I have no idea how to go about doing it.
I disagree with your assessment that the general public won't get a use out of something like ethanol or a bridge in Alaska. There are going to be things that you do help pay for to help the overall common good. That is part of being part of society. Ethanol (though I hate what the corn lobby has done) will benefit us as a nation. That bridge in Alaska might be taking oil workers to their jobs.
I pay school taxes even though I have no (and probably never will have) kids. But I also recognize, as the founding fathers did, that an educated populace is better than an uneducated one. No, the school tax doesn't benefit me directly, but due to education, there are fewer idiots out there arguing economics with me when they don't have even a basic understanding of the subject.