[Freesurfer] optseq post-hoc sorting

Hello--

I'm designing an event-related task that does not have predefined conditions. instead, I plan to do some post-hoc sorting based on performance and stimuli characteristics. I expect that after sorting, I will have 5 conditions- but it could be more or less. Is it advisable to determine the stim presentation schedules in optseq as if I had already specified predefined conditions? Or is it optimal to just completely randomize the jitter without making any assumptions about the response function?

Also is there a tool available to estimate the stat power of my schedules after I've defined them?

Many thanks for your advice, -Kathrine