To the OP...
1. I don't think space is necessarily wasted. Laptops have a lot of hot-running hardware shoved into a tiny form factor as it is. Perhaps that "wasted space" helps with ventilation. Hard to say, though.
2. A number pad would be nice at least on the 17" MBP. I can't see that happening on the smaller models, though.
3. I think the current Apple Remote is fine. The current one is too thick for you? A retractable slot for an Apple Remote is just one more thing that can break, IMHO. Besides, I rarely encounter a use for the Apple Remote on my MBP.
4. Yes, a multi-format media card slot would be a godsend, preferably one that can also read high-speed CF cards. That would eliminate the need to lug around external USB/Firewire readers.
5. Blu-ray drives draw a TON of power and I don't realistically see myself wanting to burn a BD-R on the go. I can do that with an external drive parked on the desk. Besides, this is a relatively moot point considering that Apple doesn't use HDCP compliant hardware in anything but the Apple TV to do that other half of Blu-ray (uh...Movies) anyway. Yeah, maybe in 2009....IF Apple actually cares about Blu-ray.
6. HDMI? I've been able to connect to HDMI displays just fine over DVI with an inexpensive adapter. Besides, I don't like HDMI connectors. The cables fall out too easily. DVI doesn't. You can also make DVI outputs HDCP compliant for DRM-enabled material. Perhaps they'll adopt HDMI if and when they figure out their Blu-ray dilemma.
7. I hate those chicklet keys on the MB/MBA. I can't type worth a damn on them. The current LED backlit silver keyboard is fine, at least for me.
8. 16/18" LCDs on Apple laptops? C'mon, man. Find me a 16" or 18" PC laptop. Apple doesn't make the panels, they buy them from other suppliers just like virtually every other PC manufacturer.
9. Screw USB. I think that front USB ports would detract from the overall look of the MBP. I've never needed more than two USB ports at a time. Actually, I want a second FW800 port on its own controller.

That probably won't happen though.
To add my own "realistic wants"...
1. Put high-end GPUs on the high-end MBPs, not these midrange GPUs found on $1,400 PC laptops. Apple has had this problem for years...
2. User-serviceable hard disk on the MBP. It makes zero sense that a consumer can upgrade/replace a White/Black MB hard disk but can void their warranty doing the same on the MBP. Isn't it supposed to be a "Pro" machine? Better yet, put a metal door on the bottom of the machine that allows direct access to the hard disk. I can dream, right?
3. 8GB RAM capacity on the MBP. Some PC laptops already offer this.
4. Get rid of the screen latch on the MBP and adopt the latchless magnet found on the MB/MBA. Less parts to break.
That's about all I can think of at the moment.