I got myself a 2017 iM and been looking for these types of upgrades, I'm not sure on what kind of turbo to put in (brand, etc.)I just bought a RaceLogic VBox Sport data logger so I can start logging performance differences with different mods. This way I can check acceleration runs with the car stock and also as I add each mod.
I plan on buying the AEM SRI too since it has a heat shield. It's not really a cold air intake but is an SRI. I had a similar Takeda SRI on my 2009 Corolla S with a Borla exhaust and it netted my roughly 12-14 HP from what the dyno showed. So instead of paying for 2 different dyno time blocks I bought this VBox Sport since it's so extremely accurate.
The only real mod to get serious extra power is to turbo charge it. I did that to my 2009 Corolla S and netted an extra 95 HP with a mild tune so it was worth every penny. Such a blast to drive with 230 HP now.