Zend certified PHP/Magento developer

How i control many cart rule scenario

I am apply multiple cart rule in same time checkout page
Please give me suggestion.
The following scenario give below.

Scenario # 1 - which is active on staging, but not working.
* Buy 3 of SKU: 0110025186 and get 15%
* Get 10% off on $30 order with coupon: NEWYEAR
Expectations
* 15% off on SKU 0110025186
* User added a product that is not SKU 0110025186, since the cart is $30+ a 10% is applied only to the 2nd product added and not to the SKU 0110025186 since this SKU already has 15% off.
Scenario #2 - All these rules are active and should work all together
* Sitewide Sale:
    - 15% order $30+
    - 20% order $35+
    - 30% order $50+
* Buy 3 Get of 12345678 SKU and get 15% off
Expectations:
* If user subtotal is $52, apply $15%
* If user:
Subtotal is $45, and cart contains:
    + 3 of SKU 12345678 - $10 x 3 = 30
    + 1 bible SKU 0987654 - $12
    + 1 devotional AKU 98765432 - $10
$11.11 Apply discounts as follow:
    + $4.5 ($30 - 15% on SKU 12345678)
    + $3.6 ( $12-30% on SKU 0987654)
    + $3 ($10 -30%) on SKU 98765432)
We need to be able to combined coupons and different types of offer without double discounting.