Without knowing where you are heading with your quadcopter interest, it is hard to make any recommendations.
Multiwii and Arduino work, I have no experience with the combo, but ppl do fly things using it. And if you can slog through it, MultiWii has all the bits you’d expect to find if you interested in how a flight controller works.
I use Betaflight, which you can google. It is a mature quadcopter software system, source is all there but quite huge. And a wonderful variety of inexpensive and very powerful flight control boards are available that run Betaflight. I would expect it to outperform an Arduino, but it might not matter if you are just hoisting a camera for a bird view.
There is also Silverware, a very compact and open source flight control software system, but it was designed for repurposing toy quadcopters. But ppl have done amazing things with it; I just haven’t paid attention to the developments it may have enjoyed in several years.
One way to go would be to buy a lower end quadcopter that runs Betaflight and works with your transmitter and maybe also your receiver. You’ll probably get some experience doing repairs as you learn to fly. 
Separate learning to fly and have fun with quadcopters from making a career out of building, programming, testing, crashing and the other fun parts. The more you know about flying and where you really want to end up, the easier it will be to get into all that.
a7