Eagles Over the Kennebec

Don't know as it will help, but risk management teaches a process of listing the risks (changes to be made in your case), then assigning each one two measures: likelihood and impact. Usually one to five rankings, for simplicity. You might use something like desirability and impact, or maybe difficulty and visibility -- I'm not sure what would be good dimensions for your changes. Then sort based on combination (easiest just to multiply them). So high likelihood, high impact items come first. Then decide on a cutoff point, and start tackling the top items? You might use different dimensions for prioritizing, but it does make the selection process a bit easier.