Routing error/critical alerts to a ticketing system

I tuned all of my alerts just how I want them, and now that I am ready to fully implement LM into our enviornment, I am working on creating alert rules. I ran into a problem. Using the Ping Loss Percent as an example: I have thresholds set at 20 for warn, 70 for error and 90 for critical. These happen to be out of the box. I still want these warning alerts to happen at 20%. Mostly for trend analysis and reporting reasons, but I do not want to send these off to ServiceNow for incident creation... However, I do want tickets created for ping loss at the error and critical thresholds.

The problem is when creating alert rules, I can only choose All alerts routed (I dont want warnings) or I can select only one of the following Warn, Error OR Critical. If I create 2 alert rules, one for error and one for critical alerts, I will get double tickets and I dont want that either. The only thing I can think of to fix this is create a new complex datapoint called Ping Percent (Warn), set that at 20% with no thresholds set for error and critical, and then get rid of the warning alert for the original datapoint. This seems messy. Is there a better way?