Erin & SteveC,
Yep, a down haul tool is essential for the large formula sails, even though the most recent editions have less down haul force than the older models. I also have easy-uphauls on my 11.0 & 9.2, and will get another for my 8.4. Luckly, I rarely have to uphaul since I don't drop the sails very often.
I have adjustable outhauls on all my booms for my 6.6, 7.6, 8.4, 9.2 & 11.0. Luckly, I have a dedicated boom for each sail, although a couple are probably 10 yrs old or more.
To prevent an injury, I do jumping jacks and trunk rotations for a couple of minutes before rigging, and then some more with stretching before I go out on the water. You do what you have to do to have fun.