Thats a lot of questions. You can stay on the Mac because it has the power of C++ in its language Objective C. Register by Apple to access the online documentation: it is fine and has some sample. Tip: Consider NOT using the new language Swift, because the web is full of objective C samples.
For learning I recommend the website of the famous
Ray Wenderlich. The is an universum of tutorials.
Your dataset isnt to big, but be aware that the archticture and code has big influence. For the primary dataset you should use a struct and than form arrays of structs. Visualization can you do with graphics and with bitmaps, by accessing the bits and changing it values.
Important is also to write fix data on disk and read it as needed.
At first your code must run and ferget optimization: important is a good data design ;-)