OK multi-disc changer is a bit much. Would hate for it to jam then all my discs will be stuck inside.
That aside I would like to see frame rate of 60fps or better on all games at a resolution of 1920x1080p. I hate it when the game gets blurry when panning left and right. Take COD vs BF3, COD framerate looks 10x better than BF3. Even though BF3 Gameplay blows COD out of the water.
Aside from potential mechanical issues, the fact that the video game industry seems to be creeping slowly away from physical media altogether would indicate that a multi-disc changer would be an unnecessary gamble.
If you don't want to have to get up to change discs, perhaps buying games digitally would suit your needs better.
As for ideas for the new console, we are talking about the PS5, right? I'm pretty sure it's a little late in the game for ideas that require hardware implementation concerning the PS4.
I would like to see a fast internet browser on the ps4. Ps3 broswer is freaken slow, cant watch any video online without it lagging/buffing all the time. Ps3 browser is pretty much useless, even with comcast high speed internet.