Website Builder/Creator Script

Hello, I am looking for a website builder script similar to [login to view URL] that let's users signup, choose a design, and start building a site right away. I would like all of the same functionality that sitekreator offers to the end user, but with several improvements. Also, this will not be provided to resellers, only end users, so I don't need the reseller features (although it could be a future add-on). I'd like a full administration area for the entire system, where I can create packages, choose what options are available for each package, setup billing methods, upload new templates/designs, etc. Packages should control every available option I can offer an end user, disk quota, email accounts, number of designs available, advanced options, etc, etc I want to be able to design the templates using placeholders, so if I put $header into a div, that div will be the site header, etc. Other then being able to control all content on the design, I want end users to be able to add features to their site, just as they can with this system. They should be able to add... blogs forums newsletters/mailing lists forms (using a form builder, which I would love to work similar to [login to view URL]) photo gallery (with multiple layout options) html snippets/embed codes (possibly add some presets for youtube, google video, etc) tabbed divs lightbox (they can add an image or content to a lightbox) e-commerce (simple cart using paypal or google checkout, unless a more advanced option can be provided) As mentioned, all of these options should be controlled via the package manager. If a user chooses a package that doesn't include something, and they want it later on, they can either upgrade their package or choose additional features at individual monthly costs. On initial signup, they will get a free trial with no CC info required, but when the trial is up they should be shown a page to signup for a package, choose a domain name, and pay for it using [login to view URL] or Paypal. Also on the trial signup, the user's account should be [login to view URL] or [login to view URL] but when they actually pay for it, the domain will get setup and point to the users site location automatically. The site editor should be very similar to this one, very visual to use, easy to understand for someone with no HTML knowledge. Another good, similar system for reference is speaklight.com. This system should feature a detailed help section, and a support ticket system for the users that they can access right from their site control panel. I would also like the end users to be able to setup email addresses and use a webmail system right from their control panel (email accounts, mailbox size, etc will all need to be controlled in the package manager). Perhaps this system can be tied into a server control panel automatically, so it can do all of this dynamically. Maybe an integration with WHM/Cpanel, or pigyback on existing billing software like WHMCS. Another option might be to just use a direst API for a service like Amazon EC3 or Rackspace Cloud. Lastly, the final part of this project, after all the rest is done, would be to provide some basic designs to get the system started. Say 5-10 w3c valid XHTML/CSS templats, all setup to use the system properly. If parts of this system can be built using existing open source projects, classes, etc I do not have any problem with that as long as the end product works well, and everything works as one seamless system.