I have a some difficulty knowing which character is active in a combat, and a lot more difficulty knowing which baddie is active. I'm old-ish (played D&D 40-odd years ago), so my eyesight isn't all that great. I'm sure the same thing applies to many other users of your wonderful product. I have glasses for short/long-range vision correction, but with age I've lost "visual acuity" (the ability to see fine details).
Characters 'tiles' have the descended name indicator, but baddies just have a fine line around their box. These are not good mechanisms. First, the descended name requires the user to look across the entire line of names to determine which one is descended -- that's a lot of visual/brain work. Even worse, the baddies' fine lines are hard for me to see at all.
I would very much like to see something much more prominent highlighting the active character, something that can be seen with just a quick glance even by an oldie like myself.
I'll add to the above suggestion that the circles under selected characters rely on fine acuity too, in that they're just one thin circle for unselected characters, and two thin circles for selected. My eyes would prefer the selected characters to have thick circles.