All I can say about Is' comment is wow. You really are surprising for a high priestess of...Isis is it?
Ancient Egyptians were not really like that. There exists a lot of texts which were written during intermediate periods where there was no Nisut-bity or Nisut-bityt, and these texts essentially question the existence of the Netjeru and the Duat, and even of an afterlife at all. The w'ab and w'abet (those serving within the temples as "priests") weren't even always in it for the Netjeru; a lot of the time it was hereditary, or they were placed in their position due to influence of the Nisut-bity(t) or money. A lot of them sold the experience of the divine; if one paid the w'ab/temple a certain bit, they could sleep in the temple overnight in order to get pregnant, have prophetic dreams, etc. A lot of w'ab(et) in larger temples didn't even have anything to do with the naos or with the image of the Netjer within. A lot of the larger temples had w'ab(et) that were simply bakers, scribes, etc, people who on a daily basis would never even enter the Holiest of Holies. On average w'ab(et) would work for one month, be off for two months, then repeat, so it's not like they were constantly serving. And the common man? I doubt he was in much fear of his family's Netjeru or the Netjeru of the temples/shrines nearby, because they aren't meant to be feared. Appeased when angered, yes, but not feared.
You don't have to be a part of the pantheon to invoke their essence, or even their ka. However I wouldn't go around taking on the spirits of the Netjeru all willy-nilly. While they may accept such a use of their essence or ka, it can open you up to other beings coming through, which can be bad. You'd also be better off building an altar/shrine to the specific Netjeru you are looking to work with on this, giving them offerings, and asking for their assistance.
You could also always write a script, invoking the essence/ka of the Netjer by stating that you are that Netjer and that you are doing such-and-such-mythologically-related-thing. If you want examples of this I'd be willing to send it to you.
Servitude is not what Kemetic deities ask for, nor do they necessarily require constant worshiping/honoring. Ancient w'ab(et) were only required to go into the naos and care for the Netjer within once or twice a week (as in offering food and water), and were only required to change the Netjer's clothing, bathing the Netjer, etc, once every 5-7 days. Larger temples did this more often (as they obviously had the resources for it), however this is the average for most temples. Within the Kemetic Orthodoxy (a modern Kemetic revivalist religion not to be confused with anything Wiccan), w'ab(et) are required to do special rites only 4 times a week, and this is when they are not on their off months or when they are able to achieve a state of purity. So it's not even a strict requirement.
I also doubt that the Netjeru would ever curse your kids for your stupidity. Such implies that they are stupid enough to blame the blameless.
Also, slaughtering animals is something that was done as needed due to food and/or heka requirements (and even when used in heka it was often dual purposed for food). The ancient Egyptians never needlessly slaughtered animals and never wasted the animals' flesh. Very little was ever left to decay, what little that was was offered to the Netjer in the naos and/or to the Akhu.
Also, if you are going to claim to be traditional by implication and claim to be a third generation priestess, you might look to calling Isis either Aset, Auset, or one of the other translations of her Egyptian name. Isis is English which comes from the Greek Ese, which was what ancient Greeks thought was how to pronounce Aset/Auset/etc. It's not anything near her actual name.
As for Druid's comment, in ancient Egyptian texts, this happened sometimes. And that's acceptable because if you are Atum, you can tell Banebdjedet to go do x. Or if you come on the behalf of Aset, you can tell Tai-bitjet to assist you with a scorpion bite (scorpions didn't sting in the ancient Egyptian mindframe, they bit).
While modern neo-paganism applauds all deities as higher than high and untouchable, the Netjeru weren't to the ancient Egyptians. It was possible in ancient Egypt to become a Netjeru in your own right, something exemplified by Imhotep's status as a Netjeru after his death.
All in all, I'd say research. A lot. Buy a lot of books and read them all. Most of the books you should be reading should be more on the scholarly side if you want to learn the ancient Egyptians' ways, and most of the New Age books won't get you very far if you are looking for traditional ways to do things.
I'm always open for questions on Kemeticism or ancient Egypt, and I'll straight up tell you when I don't know something (and then I'll run off to find out the answer myself). I'm a revivalist, so I try to bring back the concepts, the beliefs, the practices, as much as I can while knowing that sometimes it is better to accept that we just don't know .
Scripts are generally how they brought a piece of the Netjer into themselves in order to act as that Netjer. I've mentioned them a few times already, but if you are looking for doing something "as them" I'd say go for it once you know how.