If I recall correctly, the issue with that type of afpr is it only allows you to increase fuel pressure, but you really need something that lets you decrease it when using an aftermarket fuel pump. Having said that, anyone ever try to shorten the spring to allow for adjustments to decrease fuel...
If it worked in the past, then its worth trying again. The plugs are probably fouled again from all the cranking and unsuccessful startup attempts. However, instead of cleaning them, I would just get a fresh set. Not sure what cleaning method you're using, but I've never had much luck with...
Unfortunately, there isn't much that can be done for performance. The 4g37 was only rated at 92hp. Anyway, you can get a K&N air filter and cut up the air can, and remove the silencer behind the MAF sensor on the air can lid. Cat back exhaust if you can find one (routing is the same for all...
NGK should be fine. You can get them from Rockauto. They have other brands to choose from as well, but I would avoid getting anything from the "economy" category.
It would probably be a good idea to confirm the MAF is indeed dead before doing anything. Had an issue where the car idled ok, but fell on it's face trying to go over 15mph. Datalogger confirmed it was a dead MAF (didn't read anything). As far as upgrading, not sure if there would be any...
That smell is unburned fuel coming out of the exhaust because the plugs aren't able to ignite it. Even if they look okay, they're cheap enough where it would be better to just replace them.
Going by the pics, I doubt the FIAV has been blocked off because it doesn't look like the throttle body has ever been removed and I can still see the lower half and no obvious block off plate. It sounds like the engine cranks over, so I'd probably rule out the battery being an issue. As far as...