How to control 200 relays with micro controller?
CPLD devices are cheap per pin, but you may be better off to use some more modular approach, such as 8-bit addressable latches (74HC259) or 8-bit shift registers (74HC595) or power shift registers (TI TPIC series).

Whatever method you use, you will have to take care with layout, in particular as to the grounding, as you will be dealing with significant currents from the coils and perhaps significant EMI from the contacts. If you have many boards, it might be worth considering opto-isolation of data lines on a per-board basis.