Idea is good, but take note that Wagic's native resolution is 480x272, that fits a typical PSP, 4.3" screen. There are NO other resolutions to choose from; instead, the game window is "scaled" to fit any other window size (ex. if you play in PC and click in Full Screen) but still keeping the same resolution (this is also why there are two card image sets to download in the forums, a small "native resolution" set that doesn't need to be very big and meant to be used in the PSP, and a "higher resolution" set meant to be used on computers so the images dont become utterly pixelated in a scaled windows).
Since the native resolution is "only" 480x272 (if you're playing in PSP, PSP's screen size is the real resolution; playing on PC, DON'T scale the screen and that small window you see is the native resolution), you cannot "cramp" such a small screen with details like those that will probably worsen the space problems already has. The battlefield is very cluttered already and I believe the idea is to keep the screen as "clean" as possible.
In the current "BG overview mode" we have that shows both sides of the field, I think there's just not enough space and size to add eye-candy effects to the cards. To fit those effects, the entire interface should be somewhat modified to allow for higher size and quality of the cards (for example by adding some kind of zoom option to the battlefield or even by dividing the field in two separate "screens" - one for your side and the other for your opponent's -), of course that would also mean button functionality should have to be rewritten to "fit" the new options (now that the PC port has mouse support, maybe the PSP analog stick could be used to "move" the mouse cursor in the PSP, freeing the digital stick to move and zoom around the field, or something like that).