a. The wood cups from Turbulent are nice, I've gotten 2 pairs from them, well worth the cost.
b. I use the dynamat around the cup, not on the driver, I've posted a few pictures a few pages back. I use sorbothane on the back of the drivers, found that the sorbothane cleans up the sound. I've never used blue tack so can't say how or if different from dynamat.
c. I would go with the L pads, I have a woody SR-60i with the L pads:
d. With my SR-225e I opened one extra hole on each driver, adds a nice thump to the bass and it doesn't become muddy, I think the sorbothane helps in keeping the bass clean and tight.