Rate my thermostat design

[Rachie5272]

This is my first attempt at making a prototype circuit for what will hopefully become a commercial product.  The application is a small kitchen appliance, which is little more than a heating element with a thermostat and a graphical oLED display.

The microcontroller is basically an arduino setup for ease of programming and testing.  I'll probably switch to a cheaper micro eventually, but this is the easiest way to get the display running.

For the power supply filtering capacitors, I'm using four 10 uF multilayer ceramics instead of the conventional electrolytic (heat sensitive) or tantalum (conflict mineral).  Is this crazy?

I'm more concerned about the high voltage side.  I went with a TRIAC instead of a relay for silent operation, and the zero crossing optoisolator means the lights in the room won't flicker when the heater turns on.  I'd very much like to move the bulky transformer off the PCB, but I have no idea how to source one with leads and a connector attached to it.

The mains fuse, thermal fuse, and thermal circuit breaker aren't shown.

Any comments on my design?  Hopefully it's not too bad.