Will this 3v3 level shift for arduino->avr programmer work
As a bare minimum your "dazzle" LEDs are going to require a series resistor to limit current through the LEDs. Even if the 'HC4050 can itself safely limit the LED current the LEDs as shown will clamp the swing of the signal voltage to the Vf drop of the LED. This will not be compatible with the target SPI device that you want to have 3.3V logic swings to.