what your process to generate consistant brand SaaS/UI illustrations?

Hi, I want to create on-brand images for my landing page, e.g. icons, spot illustrations etc. I want to be able to type in purpose/title of illustration and get generated options based on my brand or just consistent style. So i'm thinking of some perhaps node-based tool flow like Flora, Weavy etc. I can achieve pretty okay results with nano banana or new chatgpt image2, but they are one-offs, and the I generate the they deviate from each other (e.g. shadows, colours, roundedness, background). I need a pipeline I can run, rather than chat with chatbots.