it definitely is a complicated process, you are right about every component being an added variable. The muffled-ness you heard is more likely due to felt behind the driver along with the stock white stuff, that will make it more muffled and did not do much for the SQ, once the white felt is gone you can add stiff felt, but be sure that it is STIFF and well secured, otherwise it too will be just muffling. The akasa on the back will cause the cans to be quieter, no doubt, but that is because of the reduced reflections and not because of over damping IMO, if you really think it is overdamping, I put plasticine on the back of the cups and dimpled it with a small philips head, causing it to look something like an anachoic chamber. It still dampens, but not as well as the akasa, it may be what you like though, it does not sound bad. I also think the stock felt in the front is muffling, I took it out and used the srh840 pads with their stock felt (which breaths well, but tones down the sharp highs) and that works well for me.
at some point you will sit down and listen to them for an extended period and say: "I like this" and the modding will be pretty much over, I am at that place until further notice.
