If my large battery pack had a flashlight I don’t think I would use it. I normally keep my battery pack and phone together. I would just use the flash on the phone. Remember large battery packs are heavy. Add a flashlight would add weight that I don’t want to deal with.
If there was an Anker high light output flashlight with the option to charge a cellphone or tablet as a backup. I would be interested in that. What I really need is an oversized 300+meter beam length (i have a good one) with the option to charge my gear with. Our power goes out after bad storms and I need the option to walk the property in the dark and light up everything in my path or use as charger if my battery packs run out.