Extending micro2440 stamp board, with functionality

Has anyone tried expanding micro2440 stamp boards's functionality ?
We spent a little while using micro2440 on the SDK/base-board, s.a. adding
USB-host port, a WiFi module etc. ?

We are thinking of moving the micro2440 to a stamp and study the mini2440
schematics to add some of this functionality, selectively, and then put it
on a protoboard for some low volume production (point-to-point soldered),
for a pilot run. However, have some concerns with this approach.

1. Wondering if it'd mean some changes (even config changes) at the kernel
level ?

2. What if we do not find exact component's used on the the mini2440 ? How
difficult might that work with replacements. This is a concern because we'd
quite likely have to replace SMD with thru-hole components, and for IC's
try to find easy-to-solder packages.

If someone has attempted something like this, as can share experience, it'd
give me some more confidence to go ahead. Or, is it time to bring in the
design-experts ?

correction:
"We spent a little while using micro2440 on the SDK/base-board, s.a. adding
USB-host port, a WiFi module etc. ?"

meant to write:
"We spent some time using micro2440 on the SDK/base-board, but now would
like to remove the SDK/base-board for remainder of the development, and
work by expanding micro2440, by adding USB-host functionality, WiFi module
etc."