If this should be the right place to post a Bug: in Firmware 30.0.011:

If the font-size is getting changed via the display-settings also the icons in the main-menu used to change they're size. Just like the font they had 3 levels: Small, Medium, Big. Now, with FW 30.0.011 the icons are only able to become Big and medium but not small. If the font is set to small the main menu icons remain in medium state.

If this shoudn´t be the right place for this Bug please be so kind to tell me if there is any forum or something like that where bugs can be posted and being reviewed by Nokia Staff.