I might stick a BCD encoder on it to add more inputs or stick it directly onto some opto isolators across the status LEDs,

I should be able to get Main Power status, Tamper, Attack and Daytime mode status back. With the BCD addition I could also monitor individual zone alarms as well.

EDIT: Sorry Brain fade, a BCD encoder won't help. I'll just blow a PIC to stat mux the data instead.