Wow, thanks for sharing your secrets on making your meme. I’m fascinated by learning to make memes and was pleased to see that you used Gimp. How interesting that you used Excel to bring it together, I would not have thought of it. Great job!
Yes, Excel is very useful, particularly in the final mock up stage.
I never got the hang of using Layers in GIMP. I guess I'm too lazy to learn it, but in Excel it's pretty easy as you can quickly move one image in front of another, etc.
Another area is created Drop Shadows. For example you can copy an transparent image into Excel, put a shadow on it and copy it back into GIMP. Very effective.
Text boxes are so much easier to make in Excel. I like to try several background and Excel works well for that too.
One other thing about Excel, georgiegirl.
Excel is a place where you can store all the intermediate images and components you use in your meme project. You don’t need to maintain separate files.