I do not recommend doing anything to your SSD. You don't want utilities pushing stuff around needlessly doing writes to ununsed cells. Those utilities are mainly designed for HDD's not SSD's. About the only concession you might make to the SSD is to try to install as much ram as possible to minimize paging (writing to the backing store, virtual memory, swap space...pick your favorite term).
I did want to run the nightly/weekly/monthly scripts for OS X maintenance that are usually run overnight since I don't keep my laptop active during the night. I used to use Onyx for that, but I'm afraid of what it might do to the SSD. Any suggestions?
If your machine is sleeping when one of the daily, weekly, or monthly maintenance task is scheduled to run then it will still be run shortly after you wake your machine. If the machine is off then it is not rescheduled until it is time to run the next day.
The fact that the periodic maintenance tasks are run after waking from sleep is different that it was from earlier systems like Tiger since cron is no longer used to schedule these tasks.