i3 of 3.2 Ghz
i5 of 3.0 Ghz or .
i7 of 2.3 Ghz ?
I don't know. It depends A LOT of which processors in those families you're talking about.
How many cores do these processors have? What kind of cache do they have?
Also, there's no such thing as AE CC 2016, but I'll assume you meant CC 2015.3 (which was released at the time people would expect CC 2016 to release...)
CC 2015 and CC 2015.3 will have similar performance requirements. The renderer is mostly on one core, so IN GENERAL clock speed makes a big difference. CC 2014 can make use of multiple cores during rendering for something called multiprocessing, so the number of cores may matter.
But remember, there is a lot more to a processor than just the clock speed.