Raiser's Edge NXT workflows are an idea that has a lot of potential bit the tool is missing a lot of features that would make it useful.

However if adding a constituent a workflow to a work flow was an API endpoint apps/customizations could make up for a lot of these missing features.

NXT email marketing in general is notably absent from the APIs so it would probably make sense to add this as part of a new API or group of endpoints related to marketing emails