BA Fairmont DVD Upgrade Sanity Check

[Rompers]

Looking at installing a DVD / Multimedia head unit into a BA Fairmont with Premium Sound and Colour Screen.

Just wanting a sanity check for the upgrade and learn any other tips.

I intend to use the factory setup for sound via AUX, speaker upgrades will come later, purpose is mainly for iPod connectivity, but the odd short show will be watched from time to time.

The head unit I am looking at is a Pioneer unit DVH-P435UB (I know there is a basic Multimedia headunit I could run but I would rather navigate on the screen rather than having to look down at the deck).
It needs an add on screen for visuals, so I add into the mix a "BA500".
The car already has the factory AUX input, but I gather I should toss it out and get the Line Conditioner, "BA529", this is where I would plug in the pre-outs of the head unit.

I'll be fitting it with the Aeropro Dual Fascia USB upgrade.

A few clarifications are needed.

With the BA500, I can plug the video output of the deck into it, select AUX via the ICC and then flick a switch to see the output of the headunit on the intergrated screen.
I gather I have 2 options here, I would imagine the first of these being better as it allows switching back to ICC for other functions.
1. Keep the 12v switched input of the Video Convertor free for later use with reversing camera if I choose, or,
2. Connect the headunit to the switched input and trigger via the head unit but loose reversing camera option.

With any of the kits will it get me a 12v constant line over to the head unit or will I need to still run one from the rear of the fuse unit?

Have I missed anything?, is it better to run the camera now and be done with it? Open to ideas about other Head Units too, integrated bluetooth would be a bonus, (option on the Pioneer)