Results were not what I wanted, what is my next best step?

You are conflating implant size (or profile) with your outcome. First, using purpose built sizers is a validated way of effectively choosing the right size implant for the patient. In my practice, it has eliminated wrong size surgery that used to occur a few times per year when I used 'inspo pics' provided by the patient to essentially guess what implant would achieve the same result. This is why I try to tell the world to stop asking what size implants I used in patients I present in social media before and after pics. The results from any given implant is unique to that individual and no one else. The issue you're having is the lack of pre-operative analysis and feedback the surgeon should have given you: your breasts are small and far apart, and your chest is very prominent at the sternum, leading to a sloping chest wall, further separating your breasts. Looking at photos of others wouldn't have helped. Simple analysis by the surgeon and an honest conversation of outcome would have prepared you. You could have chosen larger or wider implants but they would've been perilously close to the skin near your sternum, inviting severe rippling. What can help at this point is fat grafting the medial aspects of your breasts, building up a soft tissue cuff to soften the visible outline of the implants and (subtly) close the gap.

Your nipples were very wide set before surgery which led to the wide gap. I also think your implants are too small. You can go with larger implants which may help a bit however your implants will sissy’s tend to be wide set.

Sorry to read about your issue. Judging by your anatomy, I would have told you that it is going to be difficult to get you a lot of cleavage but by maximizing the base diameter of the implant, being aggressive with the dissection but not overly aggressive, we would achieve as much cleavage as your body allows. This is were measurements, sizing and communication with the patient goes a long way.

Unfortunately now you are in a place where you would benefit from a revision but stuck as your surgeon wants to charge a full price. I am not sure what to say about that, but I would say that getting a revision at another plastic surgery practice with a surgeon that has a great deal of experience performing revision surgery will cost as much as what your surgeon wants to charge and perhaps more.
I would try to discuss this further with your surgeon or get some other opinions from board certified plastic surgeons. Hope that helps.