@Benoit Lambert , From your description, I know you want to automatically delete iPads based on "Last check in" and "Model". If there's any misunderstanding, feel free to let us know.
Based as I know, for the Intune device cleanup rules, currently it can only automatically delete the devices which haven't checked in for the days we set. Here is the picture and link for the reference:
https://techcommunity.microsoft.com/t5/device-management-in-microsoft/using-intune-device-cleanup-rules-amp-160/ba-p/377272
If you want to add other criteria, we suggest to feedback to Intune uservoice to request the new feature.. This is a place where the Product team collect the customer requests to improve Intune product.
https://feedbackportal.microsoft.com/feedback/forum/ef1d6d38-fd1b-ec11-b6e7-0022481f8472
Meanwhile, for the generation, in the device hardware details, I find it is not there. You can also feedback it to the Intune uservoice to see if it can be added in the future.
https://learn.microsoft.com/en-us/mem/intune/remote-actions/device-inventory
Thanks for the understanding and hope we can get these features in the later future.
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