Yes, there's a *LOT* to be said for sticking with mainstream hardware, and the Pi is about as mainstream as it gets for consumer SBCs. Get a PI 3 to develop on then if you want to integrate it into anything consider a Pi Zero to deploy with.
Also why not try an Arduino? The Uno is the most popular entry level one and you'll soon get a feel for how much of C++ is practical on a small MCU with only 2K RAM. Its very easy to ditch the Arduino setup()/loop() stuff
* and code in raw GCC C++, either with the simplified Arduino HAL, or digging deeper and using the raw AVR registers and libraries. Once you've mastered that, porting to any ATmega MCU is fairly simple.
Both platforms have plenty of good breadboardable tutorials to cover the interfacing side of things.
* see
http://www.gammon.com.au/forum/?id=12625