Based on your experiences, could someone suggest/recommend what are the best pra

Nikhil, could you please be more specific about your use case? It is difficult to pinpoint what data will be important, as something like this is very subjective and unique to each application.

Actually there is no such specific requirement. The end user wants the data to be available for time period over an year. However, we are anticipating large number of instance launches, hence we plan to push the Business and Process values in external DB. Currently,we have created this CDT for Process related data:
1.          Archived Process ID
2.          Process Name
3.          Process Model Name
4.          Priority
5.          Initiator
6.          Start Time
7.          Deadline
8.          Completion Time
and
1.          tp!id
2.          tp!uuid
3.          tp!name
4.          tp!description
5.          tp!display
6.          tp!priority
7.          tp!owner
9.          tp!starttime
10.          tp!deadline
11.          now()
12.          pp!id
We will be able to report on most of the things from this data in the future, however we are not sure what else might need to be captured from Process/Task Data which might be required in the future.
Since there is no specific requirement, wanted to understand from varios experiences about the process data that might need to be captured during design itself.
Thanks

This seems like a fairly comprehensive process data audit. Above and beyond this is very application specific. I would recommend having a conversation with the stakeholder and going over what information is/may become important to them.