Thank you for the idea.
As you know, e-commerce market changes every day. It dictates new requirements, it provides new technologies and it gets updated extremely fast. To keep up with it we use
Scrum approach, which lets us be flexible enough to react to constant changes on the market. When some new crucial requirement appears, we need to meet it asap, which means we should change our plans on the fly. So if we create a roadmap for, let's say, a year - under the circumstances described such a roadmap will constantly change. And a constantly changing resource can hardly be treated as reliable.
That is why a roadmap with some definite deadlines does not work in this case. But we always try to keep our users aware of the features, coming in the next version, thus we announce them in the news about versions releases. You can see the coming features in our ideas base - the ones that are in the "Started" status actually make the readmap for Ecwid.
And in general all the features, that are planned to be implemented, can be found in the ideas base top. Unfortunately, ETA for them cannot be provided for the reasons explained above.