Astria is a relatively easy-to-use interface for generating custom images with AI even if you don't have a lot of technical expertise. It's got a range of tools, including IP Adapter, Pose and Depth, and can be used with APIs. Astria also has high-quality fine-tuning and can generate videos from scratch, so it's a good choice for creative projects.
Another good option is getimg.ai, an AI image generation and editing service. It's got a powerful suite of tools, including Real-Time AI Generator, Image Editor and ControlNet for more advanced image guidance. The service also can be used to train your own AI model and can be used in conjunction with other AI models, so it's good for a variety of creative uses.