Putting photos back on iPhone... If you want some photos back on your iPhone, what I do is email them to myself then open the email on my iPhone, a have select save the images...
If you use iPhoto for importing photos from a digital camera including from your iPhone and for storing all photos on your Mac, you can create an iPhoto album or multiple albums. Place the photos from your iPhoto library in the designated iPhoto album that you want transferred to your iPhone.
Under the Photos tab for your iPhone sync preferences, select sync photos from iPhoto.
Choose Selected Albums and then select the iPhoto albums that you want transferred to your iPhone. Select Apply followed by syncing.
If you want to transfer additional photos to your iPhone, place the photos in an iPhoto album that is selected to be transferred to your iPhone under the Photos tab for your iPhone sync preferences followed by a sync. Or create a new iPhoto album for select photos. For any photos that you want removed from your iPhone, remove the photos from the iPhoto album that is selected to be transferred to your iPhone followed by a sync.
All photos transferred to your iPhone via the iTunes sync process will be stored in your iPhone's Photo Library, and the separate iPhoto albums selected to be transferred will also be available below.
You can view photos available in an album only by selecting the album, or all photos available on all albums by selecting Photo Library.
The same applies to iTunes Playlists for music.