There is a major limitation between Service Catalog and Custom Triggers. 

When building forms I want all Fields that relate to that form to fall under that forms Service Category only. From an Admin perspective it keeps things clean. But on most forms I need to include a Custom Trigger at some point. That Trigger will create an email and in that email will need to be information from a submitted request.

The issue is that Additional Fields created under a Service Category can NOT be used for Custom Triggers at all. They cannot trigger them and they cannot be included in email templates that they send out. It's very problematic. 

I still need my Custom Triggers though. To allow for this I identify fields that will need a custom trigger while I build a new form. I then make those additional fields in Service Desk under Incident Additional Fields and then add them to my form. That is what allows me to create Custom Triggers and include the required information. But this means I have fields for one form in two places and it gets very messy over time.

Now, onto my request. I need a work around for the above process. Because the above process is pretty unacceptable and bad design. 

If my goal is to create all fields for a form under it's Service Category. Then the only way I can think of to get an email sent out if the right criteria is met is by creating a Field and Form Rule. The FAFR can be set on Form Submit and will execute a script. What I need to know is if it's possible for a script to have an embedded email template that can also pull field data from the submitted form much in the way Custom Triggers do. I would also need to be able to say who it goes to. The downside is I would have to create a FAFR/Script for each instance where I would have rather used a Custom Trigger. But that is preferable to using fields under different modules.