bravo good foundation.
I would reccomend LIME juice over lemon and would also incourage those who dont want to spend time roasting and peeling peppers that they can just add a spoonfull of their favorite salsa to the avocado for a great guac.
the ACID from the citrus is essential to keep the guac from browning.
the emulsifiers and homogonizers in the commercial salsas will help to do the same.
HATCH green chilis get my strongest endorsement!
black pepper or a medly of fresh ground pepper, garlic POWDER, not salt, a pinch of sea salt. fresh herbs, not just celantro these are all nice added components if not used in excess.