The difference between a 2.2:1 and 2.5:1 gear ratio is 12% and that is quite significant. However, I'm not sure how you are calculating these numbers since a 39/24 is 1.63:1 and a 30/28 is 1.07:1

BTW, now that you have the triple, a low cost way to get an even lower gear is to change the 30T granny ring for a 26T ring as Joejack suggested above. That will lower your current low gear by another 13% and that could be a real advantage at the end of a long climb.