The track layout hasn't changed all that much except for minor things related to the NYS&W takeover of the former DL&W in 1992, moving the Amtrack station and the addition of CP-290, and the removal of the tracks into Marley's scrap yard when the mall was built. And of course the new intermodal yard was built during that period, eliminating the hump switching at Dewitt. The only other big change I can think of is they abandoned most of the former West Shore Belle Isle yard and sold some of the land to the NYS Fairgrounds also in that era.
I was a fairly avid railfan in the mid-1990s and primary Syracuse local power was always B23-7s or GP38s, with occasional use of GP40s; until the hump was removed some jobs had SD38/slug sets. They'd use anything that was available if necessary, though, one night a Dewitt puller had a UP SD40-2 for power. Very rarely a GP10 might show up, I have pictures of a couple of them. Most traveling jobs like the Solvay Hill local and the WADE-10 that worked the Baldwinsville Secondary got two units. I suspect as you go back into the 1980s when GP35s and GP30s were more common, you'd see them. SW1500s and other units almost never turned up here - they weren't unheard of, but not very common. And my dad has a super-8 movie he let me take as a kid about 1985 where we caught a Dewitt Geep (RS3m) picking up a car at CP-293.
Most of the industries are still there if not active, a few have been torn down or handed to other carriers.
When I was avid you had an afternoon and a night job to work Solvay including the east end of the Auburn branch and the former DL&W down to Jamesville, a day and sometimes a night job for the B'ville secondary, and various yard jobs working mostly in the yard including the lead to New Process Gear, the lead to 84 Lumber that used to connect to the old Earlville branch remnant, etc. I belive there was a day job to work track eight and track seven between CP-291 and CP-286. Back then you had the GM plant and some business at Carrier, as well as a batch of other side customers.
The Auburn branch only had about three customers and only one at the end, Southern Container. Further west where Taylor Rental is was once Estlinbaum's Lumber and got cars in; and there was a cheese plant in Hartlot that got cars occasionally. I'm not sure what year they ceased through service on the line, but in 1992 nothing ran between Auburn and Camillus.
And all work on the south end of the Montreal Secondary was handled by locals out of Woodard and Fulton, you had a WAFU-10/20 that would run to Dewitt and back (it might outlaw on the day crew and return with the night crew) that also did some drops at Woodard. Some of the road trains could drop cars there, too, at one time CNSE might drop hot cars for Alcoa at Woodard before coming into Dewitt.