Can I generate frequencies faster than 32 MHz with ATTINY85?
According to the datasheet:


  6.4 Clock Output Buffer
  
  The device can output the system clock on the CLKO pin (when not used as XTAL2 
  pin). To enable the output, the CKOUT Fuse has to be programmed. This mode is 
  suitable when the chip clock is used to drive other circuits on the system. Note 
  that the clock will not be output during reset and that the normal operation of 
  the I/O pin will be overridden when the fuse is programmed. Internal RC 
  oscillator, WDT Oscillator, PLL, and external clock (CLKI) can be selected when 
  the clock is output on CLKO. Crystal oscillators (XTAL1, XTAL2) can not be used 
  for clock output on CLKO. If the System Clock Prescaler is used, it is the 
  divided system clock that is output.


So as long as you aren't using a crystal oscillator which would consume both the CLKI and CLKO pins you should be able to output the PLL's clock output directly through the CLKO pin.