As for hearing the ringing sound (ringback tone) in your phone before the cell starts ringing- this is indeed also a CDMA thing. CDMA phones when active on the network are 'asleep', IE not listening. Every several seconds they wake up and check in with the tower. The setting for how often this happens is called the Slot Cycle Index. This is a number, which times 1.3 seconds + 1.3 seconds = the slot interval.
Thus, 0 = 1.3, 1 = 2.6, etc
Sprint phones have a default slot cycle index of 2, which means their slot comes around every 5.2 seconds or so. As a result it can be up to 5 seconds between the time the tower gets the incoming call (and the caller hears ringback sounds) and the cell phone starts to ring.
Some 'smarter' phones take a second to then wake up and start playing their ringing sound. This of course increases that time. For example my Mogul makes the bluetooth headset ring as soon as it gets the call, but it doesn't play its own ringer for another second or two.
You can decrease your slot cycle in phone programming if you want. I have mine at '1' so my phone rings a bit faster. However a lower slot cycle will use up a bit more battery life. It's possible to change if you know what you're doing, but you'll have to be familiar with the programming menus of your particular phone and also have your MSL
code. Note that you can break your phone trying to do this if you do something wrong, and if you call Tech Support for a fix they will send ex-CEO Gary Forsee who will get drunk in your living room, pass out on your couch and refuse to leave. The programming procedure also varies from phone to phone.