If nobody rejects you, nobody chooses you
Positioning that offends nobody attracts nobody. The brands that escape commodity status all take a position some segment dislikes.
Write down what you are deliberately bad at. If you cannot, you have not positioned anything.
Find the attribute buyers can feel
Speed, depth, narrowness, a particular kind of customer, an unusual process. It has to be something the buyer experiences rather than something you assert in a strapline.
Ask ten customers why they chose you over the alternative. The answer is usually one specific thing, and usually not what your marketing leads on.
Then over-commit
Build the whole business around it, including the parts that cost you. A differentiator you would abandon under pressure is only a claim.