Hi Gloom,
I was looking on the web and saw this post. I am actually a re-seller myself with Duda and will be honest there is no better alternative. I love it. I have been a re-seller since August of last year and I think many of the things you are looking for and more in mobile design are available with Duda. I use them everyday and all I do is web and mobile web. I don't need to use other tools when creating mobilites because Duda provides everything I need. Other benefits to being a re-seller are private label tools, custom pricing, discounts, marketing and platform training support and priority technical support. Contact them and ask them any more questions that you have. They'd be glad to hear from you.
Morrison