If you're looking for a Muse Pro alternative, OpenArt is definitely worth a look. It's got a variety of relatively accessible AI drawing tools and editing abilities, so it's good for artists of all abilities. With boundary-free AI drawing, advanced AI art tools and the ability to create your own styles and models, OpenArt is a good foundation for creating and editing your art.
Another good option is getimg.ai, an AI image generation and editing service. It's got tools to generate new images from text prompts, edit existing images and train your own AI models. With tools like Real-Time AI Generator and ControlNet to steer AI generation, getimg.ai has a lot of tools for different creative tasks, including generating high-resolution images and using community-trained AI models.
If you want an open-source option, Picture it is an AI art editor based on stable diffusion models. It's got tools to fine-tune image generation, auto-suggest prompts, outpaint and inpaint, so it's a good tool for digital artists and designers. The open-source community helps keep it up to date and accessible.
Last, ArtRoom AI is a powerful tool for generating, editing and refining images with AI. With full-service painting with layers, ControlNets for steering, and a gallery of different styles and mediums, ArtRoom AI can generate high-quality images and steer them. It's also got a free tier, so it's a good option for artists who want to take their creative work to the next level.