

I’d take out the 13 stripes from the US flag and just use the naval jack.

In general I think any flag that is using seals, crests, or text should probably have a redesign, not necessarily to remove the icons, but to simplify them. (US state flags are the worst offenders here.)
Belize has a flag that looks like it could be the flag of a midwestern state.

The flag of Cyprus is just an outline of the island which, I feel, relies too much on cartography for its symbol. What if you’d never seen a map?



The square Swiss flag works well because of the cross. If it were oblong, it would look unbalanced with the cross in the middle.