Sam's Anti-hacker Account Mods V1.4

Features:

Provides a option to Remove password input requirement, if enabled visitors are redirected to checkout on completion and makes the personal details input a seamless part of the checkout.
A new option is added to require the user to input a 'strong' password, or ensure generated passwords are 'strong'.
The date of birth field is now a drop down which automatically formats according to the store country, this ensures the format is correct, slashes (/) can still be sanitized and the visitor cannot transpose days & months.
The telephone field is checked its numeric (if entered) and contains only limited allowed chars.
The fax field is checked its numeric (if entered) and contains only limited allowed chars.
The post code field is checked for the correct format, but only for UK, USA, Canada, Australia & France addresses, valid inputs will be reformated to standard code format.
If strong password is enabled, password forgotten will generate strong passwords.
The State/Province/County: field is pre-filled with the zones for the store country, rather than a blank field that gets populated on submit!
The Country drop down is pre-selected to the store country.
Ajax code is used to auto update the county drop down on change of Country Selection, operation is as similar as possible with javascript off.
Name, Address, Suburb and City Fields are subject to additional validation, limiting word & character count.
Has new modules for name & address validation used by all account pages.
Has new 'single' address input module (again used by all account pages) that orders the input adddress fields according to the supplied country address format.
Contact Us is expanded with details based on ideas in Super Contact Us add-on, but orders id is taken from dBase & provided as drop down.
All input fields (post vars) are sanitized, any 'latin' characters are allowed

Add-on is at http://addons.oscommerce.com/info/7202

In regards to purchasing without an account it is a commonly held belief that it not requiring customers to create an account increases sales, it has been tested time and time again, every conference I go to including the Internet Retailer conference says to get rid of the registering. Here's just one of the articles from Bryan Eisenberg's company (Future Now or grokdotdom.com) about it, which I'm sure you know he is very knowledgeable in the optimization field, there are dozens more articles about the forced creating account causing lost sales on their too…. http://www.grokdotcom.com/2007/10/03/yes-or-no-why-must-i-choose/

I think you are thinking too much