Jalma,
LC does not make use of any experience letters. They come into picture only in I-140 stage. However, it looks like your lawyer got copies of your experience letters already. INS needs only copies of experience letters/marriage certs etc., Do NOT send any such originals w/ your applications.
parvardigar,
I-693 is a must for I-485. Submitting it along with other applications MAY NOT expedite the process. Nevertheless, not submitting it MAY slowdown your process as INS will generate a RFE at some point. I don't know if they could issue a RFE when they do a mandatory review of application before issuing EAD. If they do, it will result in delay right there. Unless you have strong reason, I would say better to send every thing in one packet.