Hi @darrow33,
I hope you are well today and thank you for your questions.
1. I saw that the suggested image size for featured images was 730 x 410, but mine don’t seem to stretch on the slider. In the dazzling demo, it seems like even though the featured images are also 730 x 410, they seem to stretch across the entirety of the slider. How do I make it stretch?
The featured image sizes of slider posts should be 1920px X 550px as displayed on this demo site https://colorlib.com/dazzling/
Another problem: The logo I upload keeps getting resized to be quite small, and it appears there is no setting to upload retina logo either. How can I do this?
You can change the logo size by using the solution posted in the following topic.
https://colorlibsupport.com/t/how-can-i-change-the-size-of-the-header-imagelogo/#post-52872
For Retina Logo could you please try using the solution shared in the below topics?
https://colorlibsupport.com/t/retina-logo-and-images/
https://colorlibsupport.com/t/adding-a-retina-logo-to-the-site/
Best Regards,
Movin