we are having same dilemma. we don't really need the range for our use case, 6 mile daily commute, seldom have road trips. however bigger is better, even if you don't use it.
a fews days ago, the difference between a new order vs inventory was around 4k and at 4k price difference we decided to order the SR over an inventory 100D. today the difference is more like 10k-11k, which means the difference between a 100d inventory or a 75d new order, this makes it a much harder decision.
-new suspension, might be better or worse. most likely incrementally better
-new permanent magnet motor upfront. better range
-faster supercharging with new wiring. however, my understanding is that the SR battery if 75kwh would charge slower if it's a 350v pack vs the 400v pack of the 100kwh LR. UNLESS they are doing software lock on the SR and using a 100kwh pack. not clear on this.