Hi @DannyFowler - welcome to the QuickSight community! Thanks for your question.
As per QuickSight documentation, you can have 30 visualization objects per sheet. However, you can add more than 30 visuals with the limit being 50. You get a warning of possible performance regression. Please refer to the post.
I’ll mark it as a feature request.
Please create a support case and follow up as needed.