The following is due to notes from people visiting this Forum.
Basically, constantly can observe Folks saying things are 'missing' from Edge C. Things felt to be absolute parts of Edge, like "Standard Equipment" on a car. I will mention all the things on the list were not all in Edge when it was first released; there were things that came later which, Windows Insiders had seen. Now, we have that scenario with the Edge Insider Program.
With EIP Channels that update the most frequently see changes & additions 1st or sooner. Meaning the Channels that receive updates less frequently seem to go longer with things 'missing'.
Daily can see Edge Insiders, especially, newer ones point out the same bunch of stuff as 'missing'. All in regard to the top bar of Edge from Set Tabs Aside to Share. Also, the ability to hover tabs & see their thumbnails and handling of Favorites. Many people saying some or all of this is a big part of why they care to use Edge.
Admittedly, there does not seem to be a view-able "Roadmap" for Edge C and the Coming Soon list is quite sparse. HOWEVER, finally to the caveat here:
>> It takes a lot of time & work to have & make things work on a different platform. >> We are given to believe the Edge Team knows most Users want this group of Edge things in Edge C. >> We are give to believe it's all coming. BUT, likely piecemeal... and, as stated, likely, not in all Channels simultaneously. >> We are given to believe all will be in place by the time Edge C, actually, replaces Edge. >> We are given to believe patience is a virtue.
Whether it is here in the Forum or to Mr. Smiley, keep repeating. The more the Team is aware of the depth, breadth & passion of End Users looking for the same 'missing items' the better.
Anyway, apparently, they know such items are in-demand and apparently, the stuff is coming, albeit, bit-by-bit and certain Channels won't see things as soon as others. Take comfort in the fact that the GA release of Edge C apparently will have ALL the Edge things Users know, like, use and MUST HAVE in Edge C.
Oh & speaking of Features, the obvious implication from the above is Channels like the newly introduced Beta are not Feature-complete nor any definition of done & finished versions. You may find they look good, run well, seem stable, et al, BUT, not Feature-complete; still, 'missing things'. Insider Builds, regardless of Channel, are beta, unfinished, unsupported versions. That qualification (only) changes with the release of a non-beta, non-Insider version.
It is no different than with Windows Insider Builds. We will receive & see changes & additions that regular installations may not have for as much as 6 months, until their next Major Update.
We are told the Edge stuff is coming to Edge C just, be aware, takes time to find its way to all Channels and items may arrive piecemeal.
Maybe, the above will help in the overall understanding of scenarios, processes, what we can expect & time-spans (without things).