My reaction to muse spark is similar to how I felt about llama 4. Training models if hard. If you change a lot of things / reinvent your stack, your first release is unlikely to be perfect. But, success is about momentum / iterating rather than the quality of the first model. To reach the frontier, you have to start somewhere. IMO, it's too early to criticize, it'll be interesting to see how MSL continues building upon this initial release.