This "remake" is nothing more than a rework on the sprites, a graphical update.
From what I've heard, they didn't fix the terrible pathfinding in the original game that made units stuck in tight spaces and couldn't do simple tasks such as go around a wall to reach the other side. They could have used AOE2's pathfinding but they haven't for some mysterious reason.
Also, in multiplayer, the game still doesn't have an in-game download for custom scenarios. And again, AOE2 has this feature and they haven't retrofitted it into AOE:DE for some unknown reason.
There is some talk about patches incoming in the following weeks and that Microsoft rushed the release before it was ready to go, so I'll give them the benefit of a doubt if they'll address any of those issues.