I wouldn’t switch from C4D to Blender, Blender is the situation where you really don’t want to spend much money on a program, so if you already have one then you’re set.
As far as whether you should stick with C4D, that depends on what career you want, C4D is extremely popular in motion graphics, but if you don’t want to do motion graphics then you can probably consider another program.
Maya/Max is not cheaper with the subscription. If you were going to use the software for a while then it was much cheaper to get the perpetual license. They’ve neglected their software in pursuit of more profit. However, Maya/3ds Max are the most popular 3D software in game development and have the best support for exporting to game engines. Modo is a good possible alternative, but really overall if you want to work for a game studio then it helps more to use 3ds Max or Maya.