Clean up iOS App Icon at smaller sizes

Hi, For the right designer this is an extremely quick $30. The app icon for my iOS app looks great at large sizes but at the smaller sizes of the icon set some lines get crusty and jagged. I created the icon in Photoshop and used a script to produce all the appropriate sizes for the icon set, however, the smaller ones do not look perfect. The app icon has some slanted lines in there at a steep angle which do not translate well in small pixels. I have seen other app icons with similar angles and they look fine, I'm not sure how to achieve this and I've spent too much time on it already. Looking for a pro who has overcome this issue a hundred times before! I'll provide the PSD and the sizes to crank out the icon in (PNG). The sizes that suck are: 144x144 114x114 100x100 72x72 58x58 50x50 512 and 1024 look fine. I've attached 512, 114 and 72px. ***** If interested, please send me some proof of your work. i.e. An App icon that required some special treatment at a smaller size, just so I know you understand this process and have the experience to clean up my icon set. Thanks -