After playing the classic mode once, this is my list of suggestion.
1) The cool down timer for the spell 'Rain' is 6 turns but the cool down for the spell 'Raining Blood' is 4 turns. Maybe update the cool down of 'Rain' to 3 or 4 rounds.
2) Add one more option for item sorting. Currently, the sort order is from oldest down to newest item. While DOS EE it is newest item then to oldest.
3) Add the dialogue nearby and what the characters had spoken in the log. This feature is in DOS EE.
4) The portrait of the characters changed after using the re-spec mirror.
There is no cancel button, it only has an accept button... All the portrait is now looking from left to right. Where the original in Act 1 had a different icon (looks better).
5) I would like to see an arena mode with PvE. You can choose different kinds of AI enemies to fight in the Arena.
6) The loading time is much longer than DOS EE
Separate the map into different parts. For example, when run across a bridge, load data for the new area.
7) Some of the portrait and 3D model look very similar.
Like the Nebora in Fort Joy and Simone in Sanctuary of Amadia. And Dallis, too.. lol.
8) Incomplete or features that need improvement
The sleeping child inside the Lady Vengenance (or Hall of Echoes in late game).
9) About enemies Can we have enemies like vampire?