Autonumber Iterates based on Other Field Criteria

Howdy! I frequently run into instances where I need two or more sets of iterations within the same table base. Primarily for my work, this comes down to different process counts, line items, shipment number, or invoice count. I have found a way to work around this for linked records, where an automation can take the result of a rolled up count field of the primary linked record and add that to a number field as an “Iteration”. However, our organization can only have so many automations within a month, and multiplying that for every single process will be cumbersome to implement and a pain if we run out of automations.
I would love to see the options for the “Auto-number” field type tie to a specific other field and another option to iterate continuously or scale to the total number of tied records. An example of the continuous iteration would be a single select for a process type, which should iterate even if one of the records was deleted, while an example of the scaling process would be for linked records associated with line items, where if item 2 of 3 was deleted, autonumber 3 could scale back to 2.
This may be a minor thing for other people, but I have to manually type or create work around automations for this at least three times a day.