The first you have to do, or at least, is what i would do, is to get rgb output from the machine by making an RGB cable.
You can easily obtain a hard-to-find db23 from a {bleep} cheap db25 by cutting the unused 2 pin part, and viola. You´re done.
Then, if you feel adventureous, you can do really fun things with the 500.
That machine its hack-o-matic of the computers. Mine its running 14mhz 68000 with different clocks on the same mobbo in order to keep the customs running ok. You can easily do a zorro and cpu slot expander, so you can add cards to the 500, like 68060, scsi, ram, ethernet, graphics, sound, eprom burners....
Like i said... damn fine and fun machine
regards
-DEQ
PD: Mmmm there is a custom kickstart module floating arounf the net for A500 and 2k machines