Would r-pi work better with 1gb or more of ram, or would that push the price into a prohibitive range?
What about usb3 or sata/esata?
The SOC doesn't support more than 512MB of RAM (or USB3). Raspberry Pi is built to a price point above all else - you could keep adding/upgrading features but you'd just end up way out of their target price.
This is because I find it gives me easier flexibility in switching between kernels with embedded userlands. I run my OS from RAM with only tmpfs for secondary storage, and I make my SD cards read-only. I do not try to use an SD card like a HDD, but I am aware that many people probably do and I am probably in the minority.
In sum, I find booting from the SD card is just easier when developing than constantly re-flashing on-board chips.
I doubt that this was the intention behind having the RPi store the bootloader on an SD card, but I am thankfule for it.
For ease of development for people like me, if nothing else, I sometimes wish more ARM evaluation boards would provide a similar boot from SD card option (where I choose the bootloader), in addition to on-board flash.