There really is very few differentiable types of automatable financial contract in existence, so few that it would be possible to count them on two hands. Escrow, Security deposit, Loan, CFD, Payment, Delayed payment, Multi-party payment (in and out), Ownership claim, Stock issuance. There really isn't that many things needed. Sure, maybe there's some that are hard to do with the current scripting engine but really not that many.

Bitcoin is great for checkpointing any kind of outside data though, so it can be a good testing ground for the real utility of new types of contract arrangement enforcable on the network.