I found out that when we give the model our custom instructions in a structured way of prompt, answer, prompt, answer - it will perform much better in terms of following them.
ChatGPT should give that option instead or additionally of/to the current custom instructions. Means that there should be a custom chat intro that can be used on all chats.
And it should inject the chat after a couple of token. That means the displayed conversation is only between assistant and user and from time to time you add the new custom instructions in an invisible conversation between
moderator and assistant_alter_ego
which gives the chance to remove them from the beginning of the conversation (I really hope they are not embedded).