I know, Magento is very weak about configurable products. The fact that you cannot force a configurable product to inherit the connected simple products full price is very annoying.
This problem won’t be solved in Magento 2, as I read on latest news, but there is always a little hope to see that featured implemented in Magento seeing the great amount of requests they have.
Anyway, many e-commerce (specially the ones with massive import processes) use an old module, named “Simple Configurable Product (SCP)” by Organic Internet.
This module is very invasive (of course they must change a core Magento behavior) and on installations where the configurable product have two or three options with many possible values, it makes Magento slower and slower.
Pay attention: it’s not the module code directly to be slow but a number of activities Magento starts up retrieving the products when that module is installed.
The Simple Configurable Product is not maintained since years and if you plan to use it… don’t. Other than affect the Magento speed, it must rewrite many Magento parts causing other plugins to not work correctly. And if you try to solve the problem with other modules (like the Aitoc Extended Rewrite Engine) you risk seriously to make the installation unstable.
So, the right path to follow is to find an import system that correctly manage the configurable products, or other ways to set the prices.
Most of the configurable product prices can be deduced from a single option, while the second and third options does not affect the price. So an import system has not the problem to distribute the price delta over more simple products.
Hence, think twice before installing that module… (I’m getting crazy with it…).