Hey Dominic,
You can always submit an issue on HABPanel’s github where these features can be discussed with the developer’s community 
Nothing stops you from submitting your own Pull request with a given feature implemented as well.
We’re all here to make our home automation system better 
I want transparent icon like on the picture I posted
This could be handled with a new theme I guess
I want a custom colour picker that look more like the picture I posted
I really like the color picker @Basem_AlSaeed proposed in his recent post.
I want the possibility of an Hidden icon that appear only under condition ( Ex : my trash can apear only on trash day )
Dummy or Template widget in HABPanel?
I want to be able to switch to another page with an icon (like ahref or something )
Take a look at this issue and then at my custom widget and to the built-in Button widget (probably the best option :)), which has this feature built in
I want to add thing on the status bar maybe ?
There’s no status bar in HABPanel yet. Propose a feature
I want french support ?
No i18n supported for HABPanel right now, but honestly - I don’t think it’s a priority.
You can label your dashboards/widgets however you want
I want/Need an auto refresh system so ex: if i’m on a tablette in a the kitchen and I select the bedroom in the UI i want that the interface to return automatically on the kitchen UI after 2 min of inactivity
This could be handled with openHAB rules and HABPanel’s ability to change dashboard dynamically in response to item’s update. Take a look at this discussion.
-May be ( i did that right now in php ) have the server to look ip adress and force a room UI… so lets say i’m on the kitchen tab he will force at opening the kitchen UI
You can configure HABPanel to store dashboards per device (stored in browser’s localStorage) or you can display one set of dashboards everywhere. Totally up to you 
Hope that helped a bit!
Cheers,
K