I really don't like the current Research system, and there must be a better alternative.
The main reasons I don't like it, I beleive, were already stated:
Firstly, you choose which category to research in, you research for a while, then you get a bunch of choices which then are instantly yours when you click them. I don't really think that makes sense, and it's not very strategic, either.
(I've had towns parked next to resources like Gold, or Orchards, and had to continually research Civilization without the techs ever coming up, continually getting things I really didn't want. Certainly I like the /idea/ of randomization, but the current system just does not work very intuitively.)
Secondly, if you run into something you want, but in the near future, and pass it by, research something simpler and more immediately necessary, and go back, the other tech you wanted won't be there anymore. As if people could be just an inch away from discovering something, and then utterly forget it a few months later.
Perhaps, if for example, you spent a few turns researching, then were prompted with several things you can research: each with a time-cost listed in turns next to them, and had to choose to research one of those things.
If you changed your mind you could go to the tech screen and go 'back to the drawing board' and either throw out the research to that tech, or have it 'stick around' in-case that tech comes up again in the groups of techs you can choose...it'll be cheaper next time.
Example: You research Civilization, 5 turns later a prompt comes up listing three techs: Farming (3 Turns), Construction (5 Turns), or Housing (7 Turns). You choose Construction, and about 3 turns in you realize you should probably go for Farming, so you go to the research screen and pick 'Farming' instead, and Construction either stays as it is (or even better slowly /loses/ research points) and will be available again next time you research. So you finish Farming, and then you research Civilization again. (7 Turns) When you complete those turns you get 4 Options: Construction (3 Turns), Advanced Farming (5 Turns), Mining (9 Turns), and Civics (12 turns).
That idea makes more sense to me, and it gives you a /slight/ bit of variability...though I am not entirely happy with my idea, I'm sure someone else can come up with something better that /does/ make me happy...but I'm just throwing it out as a counter example which I think works better than the current system.