Magento 1.9 Expert Developer Wanted - Shopping Cart Price Rules Expansion

I am looking for a top Magento Developer who can work fast and add more options to the "Shopping Cart Price Rules" as one of the options i want to add is i want to offer a discount percentage of e.g. 12.5% OFF the SUBTOTAL of the shopping cart/order and this must be integrated into the default magento section of Shopping Cart Price Rule Actions and it must work in the same way as "Percent of product price discount" as this seems to be the only option to allow percentages off. Magento is a horrible system with very limited rules and i dont like it. I need more expansions unless a module is available.

See attached where i want the added options to be added.

URGENTLY WANTED