Besides the cauliflower hand, I've seen the bracer style, quiver style and sash style.
Flowering works best with 20ish spells or less, as the most packets I can fit is about 20, more if I don't plan on using the hand at all and can carry extra in the palm.
The bracer I've seen (don't remember who had it at HQ) was elbow to hand with elastic loops. Yes reloading is a problem, but only really if the 80 or so packets isn't enough. It looked 4 wide and 20 long as far as packet holding could go. I don't think you really need to worry about reloading on the fly, you could take your sweet time with it between big fights.
The quiver style I saw used primarily for Earth Storms/Magic Storms. If you know you'll be dropping one of those, this is the best. Fast and easy access to a large number of packets and it can be refilled quickly. You can't really run around with this though as the open top will let them fall out, especially if you go down. Otherwise, plant your feet and get to work.
Sash style is...odd. It was part of a kilt and held packets pretty well and hidden too. It's not really feasible for a casting style though.