Size - Offer a small 24in, Medium 27in, and a large 30in model
Processor - Ivy Bridge
GPU - Smallest option should be a 7950m, middle - 7970m, high end - dual 7970m's
SATA 3 6gb/s should be offered. Also USB 3.0 and Thunderbolt. They should offer more connections in the back also. You never can have enough USB and Thunderbolt ports. For me personally I would like to see 6 USB 3.0 ports. and 2 thunderbolt ports.
Optic Drive should be removed and an external drive should be offered as a peripheral if wanted for an additional charge.
Ram - Minimum should be 8 gigs. With different options leading up to high-end which would be 64gigs.
HDD - In the 24in and 27in model offer 2 drive spots. 1 SSD, 1 Mechanical. In the 30in model offer 3: 1 or 2 SSD and 1 mechnical. Or 3 SSD. Or 3 mechanical whatever configuration you want.
SSD's should be cheaper, considering the technology has come a long way. Minimum drive should be 60gig, max being around 512gig.
Mechanical - Lowest drive offered should be 1tb. Max should around 4tb. All minimum 7200rpm with silent technology.
Screen: All 3 models should be IPS at 120hz with swivel and height adjustment options.
Cooling - Use all ultra quiet fans.
keyboard mouse - offer more options than just track pad and magic mouse. Let people pick from any mouse in the store and get cash credit towards to total value if the mouse is more money. Also I would like to see a wireless full keyboard with number pad and track pad built in. :O
Just a few things I would like to see.