Advice needed: Best approach for mega menu drop-down.

I have a site that has a mega-menu similar to this (http://www.mightyleaf.com/) where it has multi colums in the dropdown menu.

this is how my menu is structured.




I wanted to get your opinion/advice how can this be done best.

Rightnow all the menus are being fetched from static blocks. The Pros in using static block is it's easier to deploy. the Cons i see is, I find the links troublesome to update or edit. let's say you want to change or add a product on the list on the menu. then you need to copy the absolute url and hard code it inside the static block.

I'm looking for a solution where i can make those dynamic. Product pages are are being generated from Magento and no need to hard-code it. Feature i'm also looking for a solution is a backend interface where i can select a product and just add it on my custom mega-menu (I don't want to list all product, just selected product from it's category). I know that in some cms like wordpress or Joomla, this feature can be easily implemented.

Please advice.

Thanks!