What is a customary startup package for a USA Engineering TT position at an R1?
Nothing in your proposed startup packages sounds too unreasonable. The only thing that might be a problem is the number of years of support. You’ll want to know how much it costs to support a grad student, between tuition and stipend. The larger the cost, the fewer the years of support you’ll be able to ask for.

Also, I would expect that the department will not support a post doc, but would instead prefer you to use their funding to support graduate students.