Hi Philippe,
The title size (in pixels) has been removed in the new version. If you still want to control the size you can do this through CSS styles.
.title h1 { font-size: 2rem; }
Note, 1rem is 16px - in case of fonts I prefer using rem instead of pixels which size varies between devices.
In the responsive design there's no such thing as proper picture sizes. The essence of responsive design is that it adapts to the device. Displays a vertical image in a portrait mode mobile, while a wide strip on HD desptops. The default size is therefore not editable and gives a good estimated size for every scenario. Just try resizing your browser window to see how it works.
However it should never distort image proportions - must affect only cropping. Did you see distorted hero image?
Now that I have checked the font sizes and such I found a few bugs and made font sizes smaller for mobiles. Will update the skin soon.