I'm sorry, but I just have never seen any issues with communicating to the party during a cleave. Maybe it's your setup, maybe it's the people... who knows. All I know is we call out what we are looking for, we assign roles so everyone knows who's doing what, and it just runs like a machine more or less.
Only thing we take any time to talk about what is in a box really is when it's a KI or some really good augment item someone is looking for. IDK if ther set up or what, but our cleavers don't even bother with 2 hours. Got one spinning top of death taru that gets his TP so fast he self-chains like crazy. When I'm in there assisting with AOE's too it's an insane splatter fest.
The ONLY issue we have ever run into is the earlier mentioned issue of boxes stacking on top of each other. Having any ID on them really wouldn't do much of anything to remedy that situation, and will just inject more lag into an already poorly performing environment, and further reduce the resources available to spawn the chests (in effect lowering the spawn count that just got increased). Custom colors is an interesting approach, but that may again cause some issues depending on exactly how the chests are rendored--if they are independently colored textures for each chest type and not handled some how shaders, it's more objects injected and again reduces resources available to the zone--contributing to an already established bigger problem and making it worse, in effect reverting an adjustment that was just made to increase chest count.
What really needs to be done to streamline the process in a balanced way across the board is to tweak the existng flawed mechanics of the process--assigning physical properties to the boxes that actually adhere to collision rules, and fixing the menus so you don't have to keep re-targetting the boxes. This will not have a dramatic account on memory use to the point of a potential mass reduction of chest spawns like putting on labels or potentially adding additional colored chests (the latter depending on how they are actually colored).
