Oh, right - forgot to mention this: I'm not sure where I'm displaying the equivalent of MP yet. I'm still experimenting with it yet - it's the only portion of the battle screen not 'finalized' in my head layout.
Hah - yeah, I'm just using default RTP graphics for (almost) everything until I can get the main parts of the game finished, and I had to shrink the battlers down using scripting to get them to fit for the time being. The actual graphics are going to be one of the last things I worry about, especially for situations like this that're going to require almost entirely custom built graphics.
... now that I look at it, I realize that player battlers aren't affected by the screen tone. I'm going to have to adjust the viewport they're draw on.