The reason that the Finder info window is used is that it contains a lot of controls over the item in question, including permissions. We could spend a lot of time re-implementing what the Finder provides, but quite honestly I think it's better that the Finder is left to do its job. There are also many complications that would arise out of such a development - for example having to bring up the Authorization window in order to change some settings, as the Finder does. I do appreciate your point, but I think development time is better spent making Yummy better in other areas. Feel free to convince me otherwise

One thing that will probably help a lot with your particular scenario is that the Mac listing has a Permissions column, so you can see the permissions right there.
Additionally, if you are using SFTP, there is an option in the Preferences which will automatically synchronize the permissions of transferred items.
Regarding the floating window, yes it could be done. I see your point about obscuring the listing. It's interesting to note that there has been much feedback in the past which indicates that the floating Info window in other FTP clients is not liked, and the 'attached' window is preferred. Maybe a preference is in order.