UI

Buttons

• Personal opinion: Back/forward button with history should be default
• Right click on Back/Forward button should list history, at least on buttons with history

Integration with OS

• Does not adapt to the look and feel of the OS
• Does not use the native filebrowser (download, open, etc.) in Linux

Adressbar

• URLs should be sorted by popularity

Searchboxes

• Only one search engine per searchbox takes up a lot of space if you want more than one search engine

Tabs

• Might be slightly irritating when a preview of the tab you're already on pops up