Built-in autosave feature (for the TE version).

to asm
It was expected that there would be those who agree and those who disagree, but the catch is that those who liked the idea from the beginning will mostly just have to wait to see it in practice... while those who didn't like it will criticize it from the very beginning (even though they haven't tried it in practice yet).
There will certainly be a divide, but there's a chance that the "gap" between TE-Full and SoD will eventually disappear. And no offense to Wicc, but TE-Light is just a temporary alternative. In the end, hardcore fans of extremes will be satisfied with a sandbox of like-minded people, and developing players will find the new patch to be just what they need... the main thing is that the idea works out!

Now, more specifically: (the opinion of a SoD player-conservative who is drifting into the astral plane from 2 letters... TE) :
What dissatisfies 90% of SoD players and TE players
-Turn-based gameplay
-Interface (+ buttons)
What is expected to be new, but should please both groups
-Simultaneous turn gameplay
-Built-in autosave
-Possibly, in the future, the ability to password-protect maps and saves
-Balancing of necessary and unnecessary secondary skills
-Embedding the rules into the game itself
-Other (not yet known)

What might not appeal to SoD players?
It might not appeal to them that this isn't SoD, and that it's too lazy to switch to something else, but this isn't TE either, where the only advantages for a hardcore SoD player are:
-Turn-based gameplay
-Interface (+ buttons)
And is it worth installing 300 MB of TE-Full, disabling all settings for Light, and playing with doubts about the game's proper functionality and connection, and the complete coincidence of all the details with SoD?
As for me, I might have switched to TE-Light, but for now, the audience there is small, and here, a decent alternative is also planned.

What might not appeal to a hardcore TE player?

the level of conservatism is so high that... they drift into the astral plane

Your target audience is TE players. And with this approach, you're doing them a disservice.

I took some telling phrases from Wicc's post... I assume that over time (we SoD players) will read the topic with amusement: "why I switched from TE-Full to World Tournament."