My engine of choice is Godot, it's actually very easy to pick up and it's fast enough. The thing is that it's good for 2D games, but not for 3D. For drawing pixel-art I use Aseprite, because it's comfortable and feels good. Audacity to edit sound, SFXR/BFXR for randomized 16-bit sounds, Krita for editing screenshots and thumbnails, Bosca Ceoil for music, easy to learn, but powerful enough.