I have a really big stash of batiks. Most of what I buy on inpulse tends toward the dark with great colors , when I go to do a project I always find I am needing medium/light and lights. The 1895 type or water colors are great because there is just so many colors you are bound to find some that will go with what ever you are working on ... but over the years I am pulling back from that type as they lack interest and too many together can get ... dull in certain projects. Don't get me wrong like I said they are a great go to choice for every shade imaginable. And no surprise colors when the yardage arrives.
I have had to make a deliberate frame of mind to buy the medium and lights just as much on "speculation" as the darks that are like magnets and are for me the spark or starting fabric that all other fabrics are picked to coodinate with.
Hardest part of buying some batiks on line is the color swatch may not show all the colors in the batik, I have had more than a few surprises when the fabric shows up. The Princess Mirah line is one that is often tough to buy on line as some of the colors maybe 15 inches apart from each other. This is also tough to work into some projects.
When I am shopping for batiks on line for a specific project , I look at color groupings , as sometimes seeing one swatch next to the other helps define each ones color(s) and value . ..this is really important for the 1895 type. I call the water color 1895 blender batiks.
In the "print" or patterned I look for good color(s) dispersement , not so far a part so that when cut up they look as though they are from two different pieces of cloth. I like ones that seem to work in one quantrant of the color wheel or those that work in the spectrum of a specific color.