The main problem I see with the game right now is it lacks the charm and personality of the original DD in terms of map order and GUI.
in this it just feels like a mess of different levels stringed together with no real theme other than act 1 which almost works in my opinion, where as In the first game it was like I was climbing up from the dark work areas of the castle with Act1, to the living quarters where people would go about there days in Act2, leading to Act3 where day turns to night as we move higher and higher till you reach the summit during a storm, the wind howling on the ramparts as we make our last stand to protect the lands of Etheria from the old ones army.

As for the GUI it lacks any personality at all, where the original had metal borders with diamond shaped rivets, a wood and parchment backing, animated bars for health and enemy's left making this just feels like any other game these days, the blandness of the GUI comes in spades with the inventory and level select screen.

Two smaller things that bug me are the ring menu no longer allowing me to change the keybindings of towers quickly and the pinging no longer sounds different between characters although these I could forgive if other parts of the game had charm at all.

All in all I think this is looking more like another DD2 for me instead of a remade version of the original akin to the crash trilogy which is why I'm hopping I'll be proven wrong down the line.