Can the featured episode at the top of my Episodes page be bigger?

Yes. Your Episodes page is built from settings, so open Site Settings, then Podcasts/Episodes, and in the Episodes page switches set Featured Episode Layout to Large. On any other page, open its Featured Spotlight block and set Layout to Large. The newest episode then shows as a wide picture with a play button beside a big title, on a band in your theme's dark color, with the next three episodes in a row underneath. When it is the first block on the page it runs up under the header, the way a hero does. Standard, the default, keeps the card with the picture beside the title and the scrolling row of recent episodes.