This feels like a really good idea and could be amazing with some polish! I love how you kind of set your own difficulty. However, the balance between bullet-hell difficulty and tower defense just doesn't feel very right or fun in this iteration. Also a lot of design is clunky with certain visual elements clashing against each other. Also needs a lot more content. If you plan to keep working on this, I think it could be something really cool!
Also I'm not too sure how Limitation plays into the theme? I could see some wonky answers but IMO it doesn't feel too close to the theme