For a new SaaS app that I'm working on, I want the end user to be able to create "promotions" which they can send to their customers; they will be able to do this via direct (snail) mail, e-mail, or SMS text message.
Typically these promotions will be HTML email messages with lots of pretty graphics and whatnot. I don't expect my users to know much, if any, HTML at all (ideally they would have someone to create these promos, but I can't guarantee it as I'm targeting small businesses and organizations who might not have on-site IT staff). My application would save these promotions and allow them to be modified. To make it easier on the end user I am debating using a templating system of some kind, for example Textile, so they don't need to know HTML but can create nice looking promotions.
Now, this is basically what amounts to a CMS but not as encompassing or feature-rich. Would I be better off to use a CMS of some sort and tweak it to suit my needs, or could I get away with writing my own since it's a less-functional CMS at it's heart? My application is going to be written using Ruby on Rails, but I'm not really familiar with any good quality CMS systems for that framework (and a lot of Rails applications seem to dislike playing with other apps). What I would have to do is save the template and then let the user select it later (along with the list of people they want to send it to), and tell ActionMailer to render the chosen template as the body of the message, while providing the first/last name of the customer(s) that will receive it. This doesn't sound that difficult to create, but if I can save development time by using or modifying an existing solution I would prefer to go that route.