H1B, H4 Visa

I am planning to go for H1B stamping in Hyderabad in the 3rd week of October and am getting all the documents together. I am working in EVC model for an IT consulting firm in US. I am working at client location (and not in an in-house project). This client location is also mentioned in my H1B petition

Here are the documents I have with me

Valid original passport and all old passports held + copies
Recent photographs
US Visa Application Form DS-160 confirmation page stamped at the Visa Application Center (VAC)
Visa Interview appointment letter copy
Original Notice of Action-I797.
I129 petition copy
LCA copy

Additional Supporting Documents required at the time of interview?
The original Notice of Action (Form I-797).
Form I-129 (if Form I-797 is a blanket permit,
Client letter from client taken within 3 weeks of the stamping date
Copy of Form I-797 and I-129),
Offer letter from employer at the time of joining
Recent letter from employer that describes your proposed duties and intention to hire you.
Previous work experience letters
Original degree certificates along with mark sheets.
Relevant diplomas or certificates, e.g. computer certification.
Last 6 months bank statement which proves my salary being credited,
Last 6 months pay slips
Last 2 years W2 forms
Last 2 years tax returns (1040)
I94 copy
Copy of SSN card,
Names and current phone numbers of the personnel managers at your present and previous positions; and
Latest Resume or CV.
Few photographs of my work location (employer and client)
Rent receipt, Mobile & Internet bills - proving my current address in US,

Here are the documents I don't have.
1) Project description document
2) Contract between employer-vendor, vendor-client

Did I miss any other documents and how crucial is it not having the above 2? Would it be "okay" if I attended the interview without the above 2?
Any suggestions welcome!