Upload & Sell: On
Opinions are like ***holes. Everyone has one, and this is just mine. Take it for what it's worth!
So you know where I'm coming from and can evaluate my opinion worth, let me state that I have the opportunity to look at stock photography all day in my job. I am an underwriter for a large credit card processor, and among many duties I perform, one is to evaluate websites for merchant accounts to determine Visa/MasterCard compliance and a host of other things.
My suggestion, and what I would do if I shared your same vision, would be to pick a particular field of commerce and rack your brain for ideas and concepts which would most represent what you anticipate the merchants in that field would choose as images to represent their business image and products/services. I don't want to encourage you to be too unique either, as the images are all fairly, well, ...stock. As you seem to be finding out, the stock agencies appear to like the images to fit in a little box, yet be exceptionally presented in regard to lighting, processing, and of course the technical aspects of ppi, dimension, etc. I think I've seen every possible image of the fake phone representative and "business team" you can imagine. They are, however, very professionaly shot in studios with perfect lighting.
So, in a kind tone, I ask you where you would place your three images above? They're not really the type of images one would expect to see used for stock (at least in my experience).
I encourage you to pick a field which would interest you, and just start going through the internet on Google and reviewing websites for the photos used. Gain a perspective of what appears to sell, and note those qualities.
Again, ONLY my opinion and how I would attack this venture. I'm sure many others might wish to attest to a totally different approach, and some may even be successful at it as I write these words.
My best wishes to you for success on your path!