请教offer negotiattion

我是某半导体公司内部transfer, 从国内L1 transfer到湾区总部。刚收到HR的offer,大致如下。
Job title: staff design engineer
Base salary: $106,000
Bonus: 12%
Relocation fee: up to $31,500 (including up to $8,500 for household goods and storage moving, $2000 net cash, two months hotel & car rental, and airline tickets for my family).

不知这种情况能否negotiate, 如何negotiate?
1.Job title 能否negotiate? 公司给我办L1的文档上是principal engineer, 而offer上却是staff engineer，不知能不能negotiate成principal engineer.
2.Base Salary上和我的期望值（at least 110K)有差距，建议提成$115,000不知合理吗 （+9K)？
3.Relocation fee: 想把two months hotel & car rental改成three months, 不知过不过份?
4.另外关于vacation, stock option和401K在offer都没有提，不知是否该问清楚？一般是公司统一policy还是case by case?

望有经验的同学不吝赐教，先谢了！！