I noticed some shortcomings in ifconfig (only shows the first ip assigned to an interface if a NIC has many) so in some senses i see why it had to be updated, by i see no logical reason why both the command and the syntaxes had to change? Why not stick to the parameter standard at least?
if you're changing underlying functionality, you'll have to change at least some of those parameters ("show me the first IP address" of an interface might be a contrived example). So now you have the option to slightly change the parameters and keep some, but not all of the behavior, maybe even in a slightly different way or you can have a clean break and clean up the old parameter list with all its accumulated cruft and go for a designed and thought-out interface.
