Were I in your shoes I would...
• Get rid of the capacitor on AREF. When burning a bootloader it serves no useful purpose.
• Follow pito's advice. Get some decoupling capacitors on those power lines.
• Drop the crystal + capacitors. I would use a clock signal from the programmer (are you using ArduinoISP?) instead. Less soldering. Fewer things that can go wrong. Easier to fix if something is wrong.
• Have holes drilled around the target's corners so I could potentially put in "pillars" to keep the target aligned.
• Include a sketch with the bootloader that blinks the LED on PD3 as confirmation that bootloading worked.
Will pins 8 and 9 supply enough current to do this task? 8 will be the ground, 9 will be +5 volts.
There have been various problems reported on the forum when VCC / GND pins were left unconnected. I suggest making a valiant effort to get them all powered.