Service SLA and ITSM

While on the right path, limiting the priorities to HubSpot’s default without any option to extend means Icannot use this feature.
Most of our customers follow some form of ITIL, and all of them use levels 1 to 4.
For us to be able to use the SLA functionality, I need to be able to make sure the levels align.

Please add to backlog, as it shouldn’t be that difficult to amend and to customised priority in HubSpot even without SLA I’m sure is a highly requested feature.