I love the smooch! I'm a huge fan of Holly Berry House stamps, and they have all kinds of intricate designs to color in- Smooch is perfect for that! It has a nice tapered point to the "brush" (more like a marker tip than fibers) and can be used to color in some pretty fine detail.
This isn't done with Smooch, but it gives you an idea:
My first pendant card. by mscrafty at Splitcoaststampers
or this:
Easter Egg #2 by ND Stamper at Splitcoaststampers
Of course, I'm biased about the Holly Berry House stamps, I love 'em! But any medallion style stamp that can be colored in would work well. I like to stamp and emboss these, then color in with the Smoochies.
At some point, I'll have to take a picture of the bell I did with the Smooch inks. It's very pretty!
And, of course, if you stamp and heat emboss, it makes it that much easier to stay inside the lines, lol!