Yep, I thought you might have used it singly. Using
only a single, primary flavoring (especially a fruity one) to make an eliquid, doesn't usually work out well, IMO. It's like trying to make a pizza...with
only the dough...no tomato sauce, no cheese, no pepperoni or sausage, etc.!
Most eliquids are made with a primary flavoring or 2, a "blender" flavoring or 2, and many times..a flavoring or 2 that are additives.
You can usually look at any eliquid recipe and tell which flavoring(s) is/are used as each of those types.
I hope the NannerBerry works out well for you.
As far as steeping needed...nope, I shake it and vape it. Most people who make it do the same. But,
you may like it even better after 2-3 days. Everyone's tastes are different.