Keeping it stock is honestly an option - it's pretty fast on its own.
But if you want to make it faster but quiet, probably black snorkels, K&N drop in filters, a black intercooler like Mishimoto/Agency Power/Wagner, Magnaflow exhaust, a WMI kit and a JB4/Lap3 would be my picks (personally prefer the JB4 for the WGDC controls, but that's just my opinion). Should still keep a low profile, but have enough unlocked airflow to fully utilize those piggybacks.