You should change the base model to SDXL, it doesn't really work on Pony.

The model is somewhat undertrained, you'd get better results by letting it cook a little longer. I'd also recommend using a better base model, either vanilla Pony or a better SDXL finetune that is close to the style you want.

I'm not sure what your training data looks like but for a character it helps to make two copies of all your training images, one of which has just your trigger word (m_darla) as a caption and the other has the trigger word plus a detailed description. This will make the trigger word very strongly generate your complete character while keeping the flexibility of detailed descriptions.

Your work looks promising, keep it up. :)