Is this a screenshot inside Illustrator? It's very low res and you can see some stuff from your software (the little blue x in the middle). I would suggest exporting as svg or creating a larger png so you can post it here properly. This will help us see more details. For example, looks like the bottom left line of the M is jagged.

Overall I think the mark looks good, but without more information on the brand (e.g. what does the brand do? What is their personality? How do they want to be perceived? etc.), it's hard to give more feedback or suggestions. Even if it's a fictional brand, it's a good idea to have those in mind, or at the very least what the brand does and in what industry they are.