Hasn't been updated in a long time, but the same goes for other compression/archiving utilities that I've been using until now, namely Keka, 7zX, UnRar, GUI Tar, and RarMe. To have all those format options in one app, is really a plus. But Entropy needs some serious work.
(1) Password-protection shouldn't only be set to specific passwords: you should also be able to define a generic password protection setting, which makes Entropy prompt you with a password input request; that way you wouldn't be forced to make a discrete setting for *every* password you want to use.
(2) One big plus is the integration of tar + xz, which I use a lot for archiving purposes, in my case with a homebrew installation of xz, and a bash script running through an Automator service. However, the Filter setting to remove ".DS_Store" (and in my case also files that begin with "._") doesn't work for txz archives, which is annoying because you can actually exclude these hidden files/resources with shell scripts. Furthermore, there is no way to specify compression ratios for xz, as you can do in the shell, i.e. settings possible up to 9 plus extreme mode (for bigger files). And since txz is often used for backup purposes, it would be nice to have the ability to append the archiving date and time to the archive name. Last but not least, for unix file distribution, it would be nice to have the ability to force user/group settings to specific UIDs and GIDs, e.g. generic 501 and 20, force root & admin group etc., plus options for subdirectories, or simply to retain current user/group settings (for backup purposes). At least you can specify the destination folder, which lets you txz-archive files/folders in source directories with root/admin permissions.
(3) It would also be nice to have user-defined presets in the Finder's services menu, e.g. 7z, 100 MB split, high ratio, password prompt etc.