Well, from a story perspective, the rankings in FE7 make perfect sense. Having money left over after a war is very good. Having your army relatively full is helpful so that you aren't weak after a war. Winning quickly is helpful in a war. Killing enemies with as few of your own makes sense, although Funds and Tactics also really enforce this. EXP makes sense so your whole army is effective. Now, from a gameplay perspective, these are mostly limiting, but it DOES make sense, at least in FE7 and this, as far as story goes.