That's very true.

A warranty cannot be voided by an aftermarket part unless the part is proven to have caused the issue. If you put an intake on and your tranny falls out (pretty likely seeing as its a Dodge) than the warranty is still fine. The dealership might try and BS you out of it but there are federal laws that protect you.
Even then, there are several mods you can do that are so easy to swap back its not really a big deal. If you bolt on a CAI and something goes wrong just swap it back before going to the dealership...

i can do whatever i want to the intake / put a cold air intake on (did that the day i got it lol), and exhaust mods after the cats / which i did.

no one cares

id you swap out the intake and exhaust and your engine blows you are SOL unless you pull it off before they know.

I have to take a poop.

the motor wont blow with a higher flow exhaust or CAI.. the stock cats are high flow, stock muffler high flow, and the huge ass resonators i ripped off are just for cabin noise reduction. you can rip off everything post cats and be fine cuz everything past that doesnt have any sensors on it that effect engine operations.

as long as you remove / mod the exhaust past the downstream o2's, you should be in the clear

you could probably get away with full headers and exhaust, because well, whatever difference it makes is what the pcm has fuel trims for...lol

Higher crank HP is going to have an effect. Granted the little added from a CAI isnt going to be enough to do anything bad, the dealer COULD use it as a reason to void the warranty on the motor. Im not saying I would skip modding it but if you ever run into problems I would advise removing them before heading to get the problems fixed.

no one cares

u can get loads of hp out of the stock motor just using a predator tuner. i believe its like 60 or 70. the motor is detuned from the factory quite a bit.
exhaust and intake wont give it that much lol.