Not a big mod fan, I rarely change things from stock - unless they can be changed back easily. I did add self-flashing lamps to my BH pop bumpers which is effective, and long before LEDS became the rage made an array to use in the main saucer dome on my AFM because the standard #89's rarely lasted more than a few games due to the vibration of the solenoid whacking the mothership. When I had my TZ I started on making up a Robby (still have him here somewhere) but my natural leaning away from mods stopped me ever finishing him off.

I think one of the most effective mods are the LEDS on the mini-saucers on AFM, although once again I never got myself motivated enough to want to install them (plus the kit is pretty expensive).

The most modding for me is mainly the home ROM where available!