My group doesn't declare Fate Points until they are needed, but this is mainly due to almost everyone being one away from their refresh level. So FPs are scarce, my players self-compel to get them, I give them out judiciously, and they spend carefully. I think in the last big battle they gave up 15 fate points, collectively (across 6 players): literally everything they had saved up in anticipation of the big bad (whom they did not even get to).
But I like the idea of really including the description, making it fit, rather than just tossing a fate point. So my suggestion for this is to look at other games (Exalted, ect) that encourage stunts... bonuses for descriptions. You can do this by making the description required for FP use, or, if you're really generous, telling the players that you'll even give them an extra +1 if the description is really, really cool.
An example might be:
PC: I shoot him. (rolls are made).
GM: You're 2 away, so he dodges... but one fate point would make it hit.
PC: Yes, but, he doesn't know he's up against a Gunslinger Extraordinare (tm). I smile smugly as I pull the trigger again milliseconds after the first round, aiming the next shot precisely where he is dodging to.
GM: Good job. You hit, with zero shifts over. So you deal 2 stress, of which his armor soaks one, and he takes 1 physical stress. Go get a machine gun, this is gonna be looooong...