What you want in a soap dish is one that will either raise the soap above any water that may collect in the dish, or one that will allow the water to drain. I guess many soap dishes are designed by people who are more concerned about style over function, because they do neither. When I redid my bathroom, I wanted a really pretty soap dish, and the one that I wanted let the soap sit in a puddle, so I added one of those dollar store style ones above, and presto, dry soap. So even if you fall in love with a soap dish that's not good for soap, it can still be usable.
I prefer the ones that drain well rather than just raise the soap. If water accumulates in the dish, for instance if you use it in the shower area, the soap won't dry nearly as well even if it's raised above the water. A soap high in glycerin can even stay quite wet on the bottom side. So I would suggest that for a soap to dry quickly and well, it's helpful for the soap dish to do the same. Just my experience with it, but probably good to consider in an area with poor air circulation.