Digital BW, The Print

I've been printing with Piezography inks on an 1160 on Photo Rag and am 
still deciding whether to switch to a 7600, and want to get the 
deepest, richest blacks possible for which the alternatives I suppose 
are as follows:

1. Instead of using Matte Black with matte papers use Photo Black with 
glossy-type papers like Epson Premium Semi-Matte: does any one have a 
D-max measurement of the latter versus the former?

2. Use a coating on the prints: what are the differences in appearance 
and D-max in coating prints with Matte Black on matte paper versus 
Photo Black on glossy-type paper?

3. Print a digital negative which is then used to make a silver print 
(about which I know nothing): can one print to a transparency material 
which can then be contact printed as a silver print? What transparency 
material does one use? How large a print can be made -- 16x24 inches , 
24x36 inches?

--Mitch/Paris