So! I've been working on the interface for Telepath Tactics some more. The latest improvement is that the attacks bar is now draggable, and remembers the location you last left it onscreen. Another improvement: the bar's background is now "see through"--not just visually, but in terms of mouse interactions as well. You can now mouse over and click stuff being blocked by the bar, in other words, so long as it's a portion of the bar without a button.
I'm strongly considering changing the attack bar into a box and moving all of the action buttons into it. Put another way, I'm moving back toward something like the GUI window from Telepath RPG: Servants of God, albeit one that you can position more flexibly. It's weird to end up back with using the GUI window, but it seems to represent the best compromise between ease of use and minimal screen clutter that I've managed to find so far.