iCloud is not a good photo storage solution. It's more designed as a way to transfer photos between devices. Even aside from the fact that you're limited to 1000 photos or 30 days, it's just not good for storing and managing a collection of photos.
To reiterate what others have said, iCloud is not a great solution for long-term storage of photos. If you have an iOS device with photos on the camera roll (those taken with the device or saved directly to the device) they will be included in your iCloud backups (if your device is configured to back up to iCloud, that is). The Photo Stream feature, if turned on, will upload and temporarily store your last 30 days' pictures, but this is only so photos added from one device can be copied to your other devices automatically; they aren't stored permanently on iCloud.