The A500 came with a Kickstart ROM. The A1K required a floppy disk. The 500 could also use a 1MB Agnus chip and one could easily update trapdoor RAM. It wasn't light-years advanced over the A1K but it was a good step in the right direction and vastly more affordable. Hence why it was the best-selling Amiga and the A1K "did OK" but didn't set any sales records. "Not a single technical improvement" is ridiculous.