09 tacoma performance help!

As my first truck my dad decided to buy me a regular cab tacoma - best decision. i love it. got in trouble a couple times takin it in the mud so im thinkin about just keeping it to trails and water. anyways, i dont want to junk it up at all, so any opinions on CAI's and piping? i want a deeper growl than the stock but not a diesel. As for intakes im just looking at the K&N intake kit. its a 4cyl. and im looking for improvements. any pictures or opinions are greatly appreciated

 

<<<<<<<<<<<<<<<or you could put an engine in like mine

 

k$n do nothing but let dirt into your engine.and i agree with the above ^^

 

well i dont wanna do anything to alter my stock exhaust in worry of voidin my warrenty. would it be worth it to just get an entire cat back?

 

im thinking maybe when im older ill upgrade to a crew cab v6 but, would it be worth it to get a custom straight pipe and chop that up, or just straight up chop my stock one?