I see nothing wrong with going through a smaller builder. I do think that many smaller builders provide a more personalized attention to your needs ... before and after the fact. That would include future tuning (if need be) any repairs due to your potential damage (if need be). They will give you time to discuss their creation during and after the finished product.

I think the "name game" is pretty well a mis-nomer (in my estimation).
There are brands out there that few have heard of, and remain a fine instrument. The other side of this is; You will need to do a bunch of research to determine exactly what all the hoots and whistles represent when it comes to a commissioned accordion.
If it is your first accordion... go with your builders suggestion... when you learn your instrument (and it will be very very suitable for learning)and begin to contemplate another accordion (perhaps differant key) this is the time you can get down to the cats whisker about details for what you want.

My first accordion is like my first love... I like it and will not turn loose of it for what it is, BUT I now have another accordion that I much more prefer to play (same key) as it is my ultimate "I Want in the Key of C." Oh I still give my walnut C (first one) it's share of playing still, but I gravitate to the other one as my primo. I just dont think you will go wrong regardless if it is "a name game accordion" or one from a lesser known/smaller builder.

Incidentally, my primo C accordion is one built by a man few have heard of out of Lake Charles... afterwards I had Jude place some of his magic into special tuning and spring tension/adjustment. So there is a glimpse of some of the variations for the before/after on this accordion thing-a-ma-jig.