32bit is not what limits the system from recognizing a HDD over 2.2TB. Its the BIOS. The BIOS is a old system and when it was started, 2.2TB was an insane amount. Now its very common.
What will make larger than 2.2TB HDDs recognizable is UEFI, which is in most modern (P/H67 and Z68) motherboard. Some make it look like BIOS others, Asus, take a more modern approach.
As for the 64bit, I think that Windows 8 should be 64bit only on for servers and desktop computers. Make the 32bit version for tablets and ARM.
At my work we build all kinds of machines and even our lowest end machine with just 2GB of RAM has 64bit so it can easily be upgraded to 4GB without the need for a OS install. Plus memory is so cheap, 4GB of DDR3 is under $50 bucks in most cases. Add to that KPP (Kernal Patch Protection) and I see no reason why anyone would go for 7 32bit.