I think it will happen... the "i" is going to become passe, and dropping it adds a sense of newness to Apple's line that has been too "i" heavy all these years. They couldn't do iTV or iWatch so they dropped it, and they dropped "iBook" a LONG time ago. So why not?
Apple Phone, Apple Pad, Apple Pod, etc. all work fine. Though the iPod's days are numbered, I believe. The last refresh is probably the last. Phone prices are going to come down further.
As for the iMac, I can see it branching into two lines:
Apple Macintosh: 20" & 24" iMacs with HD or fusion drive, maybe a retina-esque, priced from $999 (or even $899). Available in aluminum.
Apple Mac Cinema: 24" & 27" 5K iMacs with upgradeable SSDs and add'l ports. Priced from $1799. I think a 32" model would be nice to have, too. Available in space grey, silver, and gold (int'l markets may like that. Who knows.)
That keeps the Mac Mini at the low end and the Mac Pro at the top. "Cinema" was the moniker for the monitor line before it was rebranded to Thunderbolt Display, so it's worth considering
Since Apple is much less reliant on their Macs for revenues, they need to seize control of the market by lowering the price and getting back to the sub-$1,000 price point while catering to the middle-to-upper range. That may ding Mac Pro sales, but I bet the numbers there are already modest.