There are no Copy and Paste buttons at toolbars (there is only Ctrl+C and Ctrl+V that isn't always convenient, and on tablets (on which the virtual keyboard) it is problematic, though it is possible).
It is impossible to replace the code page of already open document (not for the separate file, not for all opened (in tabs)).
There is no search-replacement at once in all open files (in tabs).
It would be desirable to have opportunity to open in Code Editor files of subtitles (srt, ass-ssa, etc.) for the elementary editing.
It would be desirable (if it is possible) supports of *.bat and * cmd.
It would be desirable to have opportunity (via the Share button) to send web page contents from ModernUI IE (in a consequence it is possible to add viewing of resources, the web console, and similar).
If it is possible to make, then to give the chance to users to add additional extensions of files with which it will be possible to connect Code Editor (an example: to add (in settings) srt (for example in "open the following files in Code Editor"), and srt will appear in the list of "supported formats" (for "Open In..." file managers)). And, it is desirable to synchronize, then, such between different computers on one account of microsoft.
Best Regards.
PS.
Forgive for bad English. I am Russian. I use the program the translator.