I use washable filters on all our vehicles. There is no negative impact on the vehicle at all, and a small positive impact on the environment.
A cold air intake will add noise (which some like and some do not) and make a small improvement in air flow. Your Jeep is not going to suddenly become speedy, and if that is your only modification, your carefully calibrated Butt-O-Meter is unlikely to be able to feel the difference. But the formula for engine power is pretty simply. Air & fuel in + burned gasses out = power.
On my '13, a Rough Country CAI, Flowmaster Outlaw exhaust, and 93 octane tune added about 30HP. I've backed off on the tune a bit in the name of engine longevity, but I'm still at 300-305HP instead of the 285HP from the factory. Is that 15-20HP worth the cost of the parts? That's an entirely subjective judgement. For me it was.