Severance offer, what should I ask for?

I was offered 10 weeks of severance after 10 years as a software tester, and I have a few days to sign. There are 10 people counting on me, so I am trying to be careful. There is a non-disparagement clause.

I asked for two more weeks and a neutral reference. They agreed to the reference and added a week.

An hour with an employment lawyer cost me a small fee and made me feel much safer about signing.