Any reason you decided to not include the 85P?
85P? Haven't heard of that one before! Are you thinking about the ATmega8?
Why would you expect a core meant for the 32/28 pin ATmega x8 series to support an ATtiny chip? <...>
Meant ATTINY85-20PU ... IMO, there are simply too many cores
I frequently recommend that people put the Uno bootloader on their ATmega328P 16MHz boards like Nano and Pro Mini. If a bit-more-advanced-than-beginner user has no need of majek's flash write modification, are there any other improvements in the version of Optiboot used in MiniCore vs the old one used for the stock Uno bootloader that warrant the extra complication of installing MiniCore? I did look at the comparison of majekw/optiboot/supermaster vs Optiboot/optiboot/v4.4 but I'm not sure how significant those commits are to this application.
It might be a good idea to add a link to the majekw/optiboot repository branch and commit that you got your bootloader source from to https://github.com/MCUdude/MiniCore/blob/master/avr/bootloaders/optiboot_flash/README.TXT(and your other cores) so that users can easily see if there have been any significant changes to majekw's fork or Optiboot/optiboot since that time. For example, I can see that your version is at least one commit behind majekw/optiboot/supermaster: https://github.com/majekw/optiboot/commit/6262a28c994034c9303185ce7d46a31ded0c8a00.