Disregarding that Docs and Sheets do not have any selectable themes like in the main Drive page, there are two inconsistencies:
1. Tooltips in Drive show above the mouse cursor while tooltips in Docs and Sheets pop up below the cursor.
This is actually also an accessibility issue as using a slightly larger mouse cursor will partially hide any information the tooltip was trying to show
2. Docs and Sheets have inconsistent menus. Sheets have the conventional "File, Edit, View, ... , Help" menus while Docs lack many features to fill menus but hides everything else in an overflow menu. Not to mention, you click on the document name to show a popup while for Sheets, you click on the File menu to do similar actions such as creating a new file, downloading, move to trash, etc.