My MacBook Pro has a built in SD card slot, but when I went travelling I took a 11 inch MacBook Air with me which doesn't have one. I already had an "all-in-one" card reader which I was planning to take but as we practised packing our bags (yes, we practised packing our bags) it became obvious any opportunity to save space or weight was to be taken.
So I ordered a new SD only card reader. It was certainly smaller but being made out of smooth plastic was a bit fiddly to get the cap off. So I took some sand paper to it and roughed up the surface. I also thought cap was bound to get lost on our year long trip so I cut stuck some double sided velcro to it to hold the cap to the main body when in use.
Just a little example of how you can tweak things to make them work better for you.