請教offer negotiattion

我是某半導體公司內部transfer, 從國內L1 transfer到灣區總部。剛收到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).

不知這種情況能否negotiate, 如何negotiate?
1.Job title 能否negotiate? 公司給我辦L1的文檔上是principal engineer, 而offer上卻是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，建議提成$115,000不知合理嗎 （+9K)？
3.Relocation fee: 想把two months hotel & car rental改成three months, 不知過不過份?
4.另外關於vacation, stock option和401K在offer都沒有提，不知是否該問清楚？一般是公司統一policy還是case by case?

望有經驗的同學不吝賜教，先謝了！！