96 pax v 100, BAE is 60k/month more to lease, but 20k less to maintain, about 15-20k cheaper on fuel, and needs 1 less cabin crew. It's also slightly quicker on anything out to ~500 NM, as the 10 minutes less turn time beats the BAC's higher speed.
I'd say 146-100/200 is better than BAC-475, but -500 beats 146-300. They're pretty similar. Since you can get a BAC 2 years earlier, plus the fact there'll be plenty on the used market, it's probably the better choice this gameworld. Might be different if the BAC's price went up faster, or the -146 was available a bit earlier.