As a result it needed to carry nose ballast when empty
I'm not sure about the cargo version with all the seats removed, but for the pax version it was tail ballast required when empty, around 500kg of it IIRC. I believe the J61 (partly?) overcame this problem by moving the toilet from the front to the rear.
Compared with it's competitor the ATR it seemed to be overweight with a corresponding reduction in payload. Anecdotal evidence but someone told me that the aircraft was originally designed for a new engine from Rolls of around 3000shp but they decided against developing it and so the best alternative was the PW126 which was in the region of 2600shp. Can anyone from RR confirm this? The J61 had PW127 which had a bit more power (100shp?).