My goto has always been C and SDL2. I have always been able to create the games I want to make with it and it's nice to be able to transfer skills from one game to another (and often can bring code over from one to another).
I don't recommend building a generic engine or anything.. I start with putting a window on the screen, capturing player input and from then on I focus on the core game itself. The entire code base is the game, there's no engine unless you consider the game an engine.
Would I recommend this for building a AAA game and targeting 12 platforms? Probably not. If you're dabbling with game development then I think it's an incredible way to learn a lot while building up a skill set that is transferable between projects.. plus you won't get the rug pulled out from under you like Unity just did :)
I would also add LuaJIT. Being able to easily extend C types and do things like wrap vector math or string operators around SDL types without the complexity of C++ is a treat.
YMMV, of course, a lot of people have issues with Lua and LuaJIT is pinned to an old version of the language.
