We produce a number of analysis tools which we re-brand and customise for other businesses to include in their websites.
The tools are typically product comparison, data/trend analysis and report production (in a very particular sector). At present these tools run as a single instance in house, our clients redirect there traffic to us with a URL param specifying the client for branding and customisation.
Up until now we've been using an MVC approach with XSLT views. If a customer wants customisation we add switches in the MVC and/or imports&override in the XSLT. This was manageable for a while but now we have so many versions and customisations for sooo many clients, getting stable builds out the door is becoming a nightmare
We are looking to move to MS asp.mvc3 with using Razor for our views but before this I am wondering are there any standard practices or patterns for developing and managing the kind of mess we are sliding towards?