Simultaneous turns will completely change the game and, as a result, the game will lose more than it will gain.

And the "evolution" in the form of WoG (TE) is also more likely to repel. An example of this is heroes.by, which is dying precisely because of TE, IMHO.

To attract and retain players, TE should be brought closer to SoD, not further away. You can limit yourself to useful "features" such as quick army transfers, separating individual units, etc. Saving replays of battles would be a very useful thing! But classes, changed secondary skills, specializations, magic, etc. - this is not what we should strive for!