1. Stones (Minerals)
3. Beasts (Animals)
4. Humans [our lifestep]
5. Angeloi (Angels)
6. Archangeloi (Archangels)
7. Archai (Originangels)
I'm pretty sure the GFL is made of the beings of the three higher steps. So if we see those ones from that video of 1947, we see Angels, beings from the fifth lifestep, which are human-group-souls. And when we see those ones with totally black eyes and thinner bodies, we see Archangels, beings from the sixth lifestep, like in the video of one of them captured in Brazil.
That's how they really look like I guess, but if we watch them in the akasha-records we see them human-like. It is because that is where they show their real faces - what is even more real then the physical self (ego) is the spiritual self (the real "self"), because they are higher-envolved uss, the humans of the future. Humans, who learned to go deeper and deeper into the spiritual world, so that their outer physical body gained that silver-shining form we know from them. So here's the reason we contact them telepathically.
It's just like animals perceive us as big animals (mind that among us there are the two Great Beasts), because they cannot catch the inividuality we got. Plants perceive animals as moving plants, because they cannot catch the inner movement (astrality) they got where their outer movement comes from. And stones or minerals perceive plants as growing minerals, because they can't catch the ability of living in the outer world, the ability to grow (etherity).