Congrats on your new ERA. I was faced with all the same questions and came up with some alternative solutions-
On the rear gear and trans- I went with the 3:54 and a G-Force T-5 with the optional .75 fifth gear. This seems to work really well. I rarely use fifth anyway, but its nice to know you have it when just cruising. I also have a Pond 482.
Sound deadening- I put Dynamat on all the surfaces in the cockpit that get carpeted. My footboxes get warm, but not hot like I have heard so many other people speak of.
Ceramic coating of the pipes- I spent a lot of time checking into this and there is one that is really different- Swain Technologies.
http://www.swaintech.com/store.asp?pid=10296 Too lengthy to explain here, but one of the best things I did. I did the sidepipes as well. They do not get nearly as hot as many others I have checked. Yes, you can still burn yourself, but it will be 2nd degree instead of 3rd degree.
A couple other suggestions- get the Quicktime bellhousing- does not need to be trimmed like the Lakewood and saves a bunch of weight. Use an aluminum flywheel for faster acceleration and a more responsive motor.
Good luck with the build and have fun!