Okay, they are rating you by analogy to the loss of the peripheral nerve function. I think this is wrong and you should be rated under 8004. But, as far as the minimum rating of 30% under code 8004, what they did was to break out the hand/wrist and shoulder conditions separately. If you added (but not combined, there is a difference, in your case minor) the 20% and 10%, that would equal the minimum rating. So, as far as minimum rating argument, that may be a wash. However, that is completely different than if they appropriately rated the severity of your conditions in the first place.
Mike is right about the relative benefits of getting a higher rating. You are likely in about a good of a position as you will get (under current law, which may change). In order to know for sure, you have to make an informed guess about the likely rating from the VA, as well. You do want to get a rating from them as soon as possible.
I think you have to quantify the risk, though, to make an informed decision. Under 8512, the lowest rating listed is 20%. Under 5304, Here are the ratings criteria (higher rating for dominant hand):
Severe .................................................. .....30 ..............20
Moderately Severe ....................................20 ..............20
Moderate ..................................................10 ..............10
Slight .................................................. .......0 ................0
For Hammer toe (5282) here are the ratings:
5282 Hammer toe:
All toes, unilateral without claw foot..................................... ............ 10
Single toes.............................................. .......................................... 0
So, I would look these over and try to see if there is any basis for a lower finding on these other conditions.
All that being said, I would also still tend to agree with Mike that you may be able to challenge the rating later, after you have it locked in. There is a risk with accepting the findings that they will raise an argument that you have waived your rights to challenge by accepting the findings. The Services have not been ruthless about applying this argument but I could see that changing, too.
Another question I would have is why not TDRL? I am not advocating this (though you would get paid at 50% rate; there is a benefit in my mind to the permanency of PDRL, but depending on the prognosis, I think TDRL is not a bad disposition, weighing in extra pay above and beyond 30 or 40% rating in those cases ) but is your condition not progressive? Has it changed much in the past year (not that it matters per se, but to get an idea of its progression). What do your Doctors say about prognosis?
I hope I did not muddy the waters for you. Like I said, you may be at a point where you will not do better (or only slightly) with a higher rating at the VA, and you do have your medical benefits locked in under the current finding. However, I think there is a likelihood that you should have been rated higher. I don't know the other facts concerning the severity of your shoulder or foot conditions so it is hard to gauge if there is substantial risk in not accepting. But there is risk. So long as you are aware of the potential risks, that you may be able to appeal later (however with the possibility that your acceptance will act as a waiver), then I think you have a good understanding of the situation. I don't like to make recommendations about what to do because ultimately it is your own situation. But you have a good outcome now. Whether you should challenge, you need to decide.
Best of luck and I wish you the best in whatever comes after the military. I hope to see you here as a member in the future. Your input and experiences can help others.