Hi Kenny,
After reviewing your questions I have the following suggestions:
1. I see you are using Spokes 2.8. May I suggest you to upgrade to our latest Spokes 3.5 such that new features from new devices will be supported.
2. For call processing applications such as yours we recommend you use Session Manager, device Listener APIs such that all the device level complexity like you cited is taken care and hidden from you.
3. For common call processing tasks, a set of uniform APIs and events apply to all device types regardless whether there is a base or not.
4. See the sample SkypeSample shipped with the Spokes 3.x SDK as an excellent call processing sample. As you see from this sample the implementation is device independent. After you reviewed this sample I will be happy to discuss any further question you may have.
Wei Chu