wvmarle:
Don't drive a TFT display directly. Send a description of what's to be on screen to a dedicated chip that builds the screen and drives all the individual pixels.Don't try to play MP3 from an Arduino, use a DF Player instead. The mp3 decoder chip can't do anything but decoding sound files.
STM32 should be capable of driving LCD (when I'll make library for it), there is no need to add extra hardware in my opinion. I'm not going to play MP3, that is way overkill for this task, simple buzzer will do.