The perfect cordless phone, if its out there, would be blue tooth enabled (so it can linked with a cell phone), have call blocking, and also be able to link with my cell phone phonebook, thus keeping me from having to go dial all the numbers in all over again, and/or having to look them up to dial out (i.e. phone book sharing or syncing between cell and cordless).
Vtech has all but the call blocking, and thats probably the most important feature for me.