rather than implement some arbitrary number of USERDEFINEDFIELDS, yoyu can just set the datasource in version 4 to any SQL table or RSS feed or Web Service, so you start by designing your SQL Table with whatever fields you need, then configure the module to use that table to read/store data. no limitations :)
As far as the <span> issue, all token will have a format property that you can set ( ie: dataFormat="raw" ) to simply return the raw data with no tags or formatting applied.
I'm currently adding the framework code for Worfklow, Checkin/CheckOut and Content Versioning .... video demo coming soon, hopefully by this weekend.
I'm also taking the time to code all of this functionality as re-usable frameworks, so if you're a module developer and want to support tokenized output, you can add a reference directly to the Repository.TemplateEngine. If you want checkin/checkout/versioning you can use the Repository.VersionControlEngine. All of the functionality is exposed through APIs for re-use.
I'm still hoping to have an early alpha build available for people to try out sometime in April .. still a lot of work to do. The first alpha will not have a lot of the user-friendly editing tools, so the initial release will be directly targetted at developers as there will be some amount of manual configuration.