Does VGA have to be drawn at 60hz?
You need to have the vertical sync at 60 Hz (minimum), but if you're concerned about the video dot clock speed, you can simply have fewer pixels per horizontal line.

Many microcontrollers can generate VGA quite nicely if they have a hardware SPI controller, which can be configured to pump out the pixels, while the H and V sync signals are produced by the firmware (driven by an interrupt).