Let me try to answer your questions.
1. If we are talking about processes, its not fulfilling anything E2E, you can use eTOM to define, combine and improve processes.
2. If we are talking about E2E, than processes needs to be supplemented with data models, integrations between different processes for those we can use SID framework or eTOM open APIs along with SID.
Just to be sure when we streamline the processes to remove any bottlenecks or problematic processes, its easier to follow eTOM but equally important is to understand customer's layout on which you need to work, some existing processes might needs to be broken into small processes and some small existing processes might needs to be combined.
So, its always in my opinion a balance between requirement and standards that needs to be adapted.
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Ankit Singhal
Capgemini
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