I am also a MacBook, iPad and iPhone user. There are many ways to synch photos and files. When you say you don't have a USB port, are you referring to the iPad or your laptop? The iPad has a set of adapters available that will allow you to download data from an SD card (camera data kit) and also via USB (for direct connection to the camera) if you want to go that route, and there is also iCloud and Dropbox.
I listen to music on my iPad all of the time and have an AT&T version with GPS that I have an Arkon mount in the cockpit of the RV for to use as my GPS with the TomTom app.
Whenever possible I download the iPad versions of apps as they tend to have better resolution and readability for my distance vision. I still hate wearing reading glasses.
Since I synch with my MacBook, I get a lot of content from the MacBook but can also download directly from the web or cloud when needed. The iPad does come with a USB cable to both charge and synch with a computer, so you SHOULD be able to copy photo files from your laptop using the synch cable and iTunes (which is also what will be used to synch apps, music, movies and anything else that iTunes is aware of) to your iPad.
Depending on your data plan, you will probably choose to download as much content on your computer and transfer it via USB as possible. Since you already have an iPhone, just think of the iPad as a larger version of the iPhone without phone capability.
In short, you should be able to do what you want to do and there are probably more ways than one to accomplish those tasks.