Page Load: Single Slide Slider vs. No Slider w/ Widget Added in Header

The discussion revolves around the “hero image” design versus the default slider. In one thread, it was recommended that creating a single-slide slider with slider nav buttons hidden would create the hero image concept (cf. https://wordpress.org/support/topic/image-instead-slide?replies=7#post-4599826).

However, my question relates more to page load speed. It’s been documented that sliders tend to slow down website load times, and that a static image (hero image), though large, can be faster.

An alternative method I read somewhere is to deactivate the slider and hook in a header widget to create the hero image.

Has anyone already done some comparisons between a single-slide slider, multi-image slider (like the default one), and the hooked widget regarding page load speed? If so, was one significantly better?