I came back from India in Nov and I only had the following:
1. I-485 receipt
2. AP and obviously The passport
At the point of entry (JFK), I gave the officer the passport and the AP. He took some time to look at the docs and then walked me to another office. It took about 15 mins of waiting before I was returned my passport along with the AP: the AP had the same stamp as the I-94.
As long as it's a straight forward case I don't think there is a problem. The question to be answered is what do you need to take if there is a problem.
If you are paranoid like most people are, take copies of pay stubs, and a letter verifying your employment (if possible).
All the best !
