I (as I'm the only one here doing BI things) have a very basic measurement about Technical Debt:
Once existing applications exceed their target runtime, it's time to revisit the SSIS Package and make it better. Usually for me these packages have been existing for years and when I have to re-visit them I start asking the usual questions like "Do we really need to store a Date as Int?" Once I get a "no" for something like that, my work starts on the package. 
In the last 8 Months I've reduced daily run times by a total of 9 hours but almost nothing new I've done, import 2 flat files and make a simple fact table.

Next up for me will most likely be upgrade SSIS 2012 -> 2017 with everything that goes along with that, upgrade Package model, check if Performance is viable and such.

 I feel like all I'm doing is having the customer pay for their technical debt.