Nice list! A few problems though:
Telafirma - no longer responding to orders or support requests
X-Cart Plus - defunct - site gone
PHP Site Solutions - no longer responding to orders or support requests
CartMods - should be avoided at all costs -
http://forum.x-cart.com/showthread.php?t=9764
I'd suggest removing those all together.
What would also be handy are three columns - 4.0, 4.1, 4.2 to show what versions each mod is compatible with.