Stop/Target Per Contract

I would like and option to specify the stop and target in dollars per contract. This could be done by adding a button or checkbox in the settings screen to indicate whether the stop and target are for each contract, or for all contracts, together. Currently, the setting refers to all contracts, so if I intend to risk at most $100/contract, I have to fix in advance that I will be ordering a specific number of contracts. That is a problem, because it means that if I change my mind and decide to get into more contracts than I had initially planned, the stop and target will be for the wrong values.