My builds were 30~35 mb in 4.10, now in 4.11 I get 70~150mb due no compression.
I checked on the compress option in package settings, tried shipping settings but I can’t find a way to pack with .gz compression.
Also opened a question in answerhub 3 days ago, no success 
any suggestion would be welcome 
Somethings wrong with the compression setup for 4.11, if you look at your files, you’re probably getting both the compressed version and the uncompressed regardless of the build options you choose. It has a problem with misnaming the files also like memgz instead of mem.gz, and the projects use html TemplateX no what you choose, and that is build for uncompressed. This is easy to fix but it calls for the uncompressed files somewhere else that I haven’t been able to find, as opening one of the js files crashes my editor. I rebuilt my project in 4.10.4 to fix it. I know it’s not really useful but it’s all the information I have.
It turns out I was wrong about the naming convention. It doesn’t really matter how they are named as long as the system knows how to access them. Juj answered my question and explained some of it here https://answers.unrealengine.com/questions/416588/html-build-packaging-broken-for-shipping-builds.html
As far as compression, it is a little larger than 4.10.4. project went from 28MB to 38MB in the switch. Not quite sure what you’re seeing though.