Just some thoughts:
-Most printer companies are only able to stay in business because they sell ink. The margins on a printer are basically non-existant, the hope is you own a printer long enough to make money back on ink. As mentioned, commodity hell (just think of the free cell phone). If you were to change the business model would people be willing to spend more on a device that took “open” ink?
-Regarding connectivity, make sure you do an audit on what exists already. If you are thinking about user experience, does Wifi necessarily change anything? Or is it just another radio technology? Both implications involve some type of software installation, setup, and configuration or pairing. Wifi works well because it is longer range, and means you can print things from anywhere as long as you have network access. I can print stuff at home from work if I need to.