Thanks for the data.
About the compute module, it seems to be a nice option, although I have two issues with that.
1) It is based on the original single core Broadcom ship and I need a multicore device. In this case, I would need to wait for the CM3 when it be ready and I expect this to have at least 8GB eMMc internal storage.
See the blog post for today (8 Sept. 2016). Eben was asked about the CM3 and he said that "orders have been placed." To be fair, he didn't say *when* the orders were placed, nor did he say how long it takes from ordering to availability, but it does indicated that the CM3 is--reasonably--imminent. I would guess that we'll see it arrive within the next 30 to 60 days. As for having 8GB of eMMC, those that know aren't saying and those who don't know can only hope. I've been saying for some months that I hope that is the case...but since I have no inside knowledge, I don't know. If I *did* know, I'd be under NDA and wouldn't be able to say.
2) Right now I am not in the position to create custom PCBs to use the CM devices; this is why I have been working with RPI3 complete machines ( maybe in the future this will be an option for me, but not today ).
Yes...that's an issue.
In fact, in this sense, could be better to have something like a Zero+, based on the latest SOCs and including eMMc, or a reduced Kit (just some ports) to connect a CM3. Or ... maybe to have a HAT with eMMc for the standard RP3 so the machine could boot from the HAT. In this case, to have the SD with just the boot bin file and/or to use a PiDrive seems to be the best option in this moment, because I am developing some type of "personal" information system where I need more space that what it is available in these eMMc chips.
The Pi Zero is specifically targeted at "Just how low can the price of a computer go?" As such, you aren't going to see it get anything that adds measurably to the cost of making it. I'm dubious about an eMMC HAT as I don't think the bus the SD card uses (eMMC uses the same one, so far as I know) is on the GPIO block, so there wouldn't be a decent I/O channel to run it.
Part of the issue here is the inteded purpose of the Pi: Education. It is a lot easier to use a Pi with an SD card that can be removed and reflashed or replaced than if you have to take the Pi, connect it to something else, and reflash the eMMC. If you really want on-board eMMC and mutlicore right now, you might look at the Odroid-C2. You won't get anywhere near as much software and problem support, though.
A dream machine? ....
RPI4 = RP3 with USB3 support (full boot support and guaranteed electricity to drive without compromises external disks), 2GB (or more) RAM and an eMMc socket. On the software side, to support full VC4 acceleration on the graphical user interface (I know this is in the works). It is interesting, for me the RPI3 machines are very good laboratory and/or server devices (for some applications), although "almost" good enough as desktop replacements.
One can always dream. The problem is that what most people dream about in a Pi is a $35 computer with all the capability and power of a $1000 computer.
I would be quite content if the Pi4B comes out as identical to the Pi3B with the sole change being USB3. *All* of the specs of the Pi3B are enough for my intended uses except for a need for faster mass storage access, and USB3 can provide that with ease. (I know USB3 is fast enough because I've done tests with an SBC that has USB3. The reason I"m not switching to that board is that it doesn't handle the screen resolution of my monitor, though I dare say with enough digging that could be fixed, but I'm spoiled by the Pi handling it automatically.) Would I like some of the other things? Sure, but even my "nice to have" list is pretty modest...a bit faster (say 1.4-1.5GHz), and more RAM (2GB), but neither of those is really needed for anything I want to do with a Pi. (For what it's worth, I would use a Pi4B to replace a Cubieboard-2, which is a 1GHz, 1GB, dual A7 core board...but it has SATA-II on board and I have the OS installed on a 60GB SATA-II SSD.)
And to the RPF, please continue with your outstanding work.