There really is no in between though, vanilla is original stuff chocolate is custom stuff but it also depends on your personal definition of vanilla since using any newer LM isn't really vanilla due to all the ASM hacks it introduces.
The definition of "vanilla" gets pretty mushy if you think about it for quite a bit. "Vanilla" (aka "generic") in terms of modding means "from the original source" whereas "chocolate" refers to anything which has been added to the game. It's very easy with resources (including levels, albeit split into palette, music, objects, enemies) as there is a clear definition what resource came from the game you're modding and what not.
But a full product is never going to be "vanilla" as there is always some part of the game which has been modified (typically levels). As such, the mods decided to use "vanilla" only for the graphics as it's pretty easy to use custom graphics (edit and insert graphics with Lunar Magic) whereas patches and other ASM resources (outside of Lunar Magic which is exempt since there is no other way to edit levels if you're a normal user)—blocks, sprites and UberASM—and musics require you to download a separate tool.
VLDC levels tend to be "choconilla" / "strawberry" as while you can use only Lunar Magic, you can use almost all of its features including Map16, Layer 3 and even ExGFX as long as the graphics are coming from SMW (can be at most recoloured).
Actually the definition of "vanilla" has been discussable to death in and out, especially with the advent of LM3 and its tall horizontal levels and 4-exit levels. You could argue it's anything you can do with what the editor provides, but limiting yourself to the definition of the term you stick with is a more proper way to do so. Your hack is your hack and you can do whatever you want with it.