I start all my horses in a rope halter, move on to a bosal or the Branderup cavesson... I don't think a bit is needed until they are very collected and highly schooled, and it depends on the horse whether or not I would go to the curb directly or use a snaffle first. I used to always go to the snaffle first, but the more I learn about snaffles, the more I am thinking to avoid them, completely train the horse into collection (I train in classical dressage, using Branderup methods, also well known through Sylvia Loch, Charles de Kunffy, Paul Belasik... not training for dressage shows!!), then go right to the 'finishing' bit (curb).
Choosing a harsh bit due to lack of control is never a solution to a problem. Generally all our problems in our horses lays in the foundation of the horse's training...best to go all the way back to correctly leading the horse, go forward from there until you find the 'hole' (problem), and teach the horse what it is he is expected to do, instead of forcing the horse into a position or situation.
Bits, a very deep subject, and one I do not know near enough about