Emerald doesn't really exist yet, and I believe they misrepresent their automation. They've posted a very pretty site with a bunch of mockups. They have a set of workflows that work for their internal antiviral research, but "Heroku for Science" is a completely different game.
Transcriptic, on the other hand, started taking orders six months ago and has customers at Stanford, Caltech, Harvard, and more.
There are probably others much more familiar with cloud infrastructure who can chime in, but the AWS of science and the Heroku of science are two very different challenges, and I feel the analogies probably cross over pretty well.
Definitely having the infrastructure 'warehouse' layer that Transcriptic is building (with a real API! wow!) will be valuable. And like you hint at, power users won't need hand-holding, but 99% of the market of users will. That's where packaging, ease of use, and limited configuration seem to be the difference maker (Heroku starting exclusively with Rails).
Transcriptic, on the other hand, started taking orders six months ago and has customers at Stanford, Caltech, Harvard, and more.