Added a power LED
Added a stereo headphone jack for audio (even though it's only mono which I'm fine with).
Added a region switch so I can play my japanese imports
Added s-video from the built in cxa1645
Here's some pics:




If you're wondering what makes this system special. It has in my opinion the best quality s-video out of any genesis I've ever seen. Here's comparison screenshots between a model 1 va6 with a cxa1645 installed, a nomad using the existing cxa1645, and the genesis 3 which also has an existing cxa1645
S-video from a sega genesis model 1 with a cxa1645 installed:

S-video from a sega nomad:

S-video from a genesis model 3:

I wasn't expecting this but the s-video from the genesis 3 is even better than the nomad. And the audio is just like a model 1 but clearer. The only downside is there's no longer any stereo separation.
If you're okay with mono sound and no 32x or segacd then this's hands down the best model of the genesis ever made.
