- add back previous/next block hashes to top summary table (and remove back/forward buttons recently added to header)
- make better use of horizontal space on large screens by splitting the top summary table when possible
- better semantic grouping of transactions
- button-links for previous/next blocks instead of showing the hashes in the table
- don't show block-hash or height in the summary table (since it's in the H1 title already)
- add "age" description for the age below the timestamp for clarity
- include "Total Fees" and "Average Fee" in the summary table
- include "Miner" entry even if unidentified, for consistency