Disclaimer: This theory is definitely bunk, and I will surely be proven wrong both this year and next. But hear me out.
"i" is an endangered letter at Apple: the iBook died many years ago, and we now have Apple Watches on our wrists, not iWatches. iThings are passé.
I believe we're ready for the Apple Phone. Not iPhone, not iPhone 6S, not iPhone 7... just Apple Phone.
iOS 7's design language and the Apple Watch helped set the stage for a new direction at Apple — Tim Cook's Apple. That metamorphosis is going to continue throughout the line, spearheaded by a companywide switch to San Francisco typography. 9to5Mac's Mark Gurman, who has been murdering the Apple scoop beat lately, reports that iOS 9 and OS X 10.11 will both switch to San Francisco to keep up with the Apple Watch, and there's no reason to doubt it.
But check this out: "IPHONE" doesn't look good set in all-caps, which is how the Apple Watch's logo is styled. In fact, it looks terrible. If you kill the "i," your problem is solved.
There's no guarantee that Apple will update the phone's logo to match the Apple Watch's, of course, but it seems logical that that'd be the goal.
Maybe this doesn't make sense for the 2015 device — Apple's tick-tock strategy means we'll probably only get a relatively minor refresh this year — but next year's major redesign would be more appropriate for a new name. That name should be Apple Phone.
Now, "Apple Pad" is another story. I don't know what the heck Apple does with that one.