Mike,
Welcome to the site! I must say you live in an area where they're a lot of SVXers who are very passionate about their cars.
The best site to gather specific SVX info about each MY, is:
Cars101.com/SVX.
However, to answer your questions -
1) The LS-L and LSi are essentially the same thing, but the '92 SVX with the 'touring' package was termed an LS-L, while from '93 on the name changed to LSi. Some options for the '92 model, were standard on the '93 and later models - e.g. rear wing.
2) No. I know for a fact that the base models in '94-'97 used a grey cloth interior and grey plastic trim pieces. Here is a pic of mine:
3) All years are great, but Subaru made several updates to the auto trans between the '92 - '94.5 MYs. This page talks about the changes:
http://www.subarusvx.com/faq/transmission.html
-Chike
P.S. You mentioned you have an awd dyno. Whereabouts in Md is your shop? Would you give members of this forum any special rates for dyno sessions? I was planning on doing a few baseline dyno pulls over the winter period. Thanks!