The frustration in your post is evident, but it is equally clear that you care deeply about the topic.
Classical style with no borders and larger avatars is more aesthetically pleasing than the new look with borders, red lines, and smaller avatars. While borders do provide structure, they sometimes hinder readability.
If engagement is the goal, an interactive map could help, or consider sorting explorers by location. Internal tracking for click-through rates could provide valuable information regarding user behavior.
The explorer images add personality, but if they're deemed excess, their dimensions could be toned down. Click-bait quotes work wonderfully, but there is no need to expand them—they are short and punchy which is perfect.
Social media promotion and niche forums can be effective for driving traffic, so SEO is not a complete hassle. If the goal is to practice coding, keep doing what you are doing until you reach a level of satisfaction.