I have a better idea, and it would be very easy for eBay to implement.  No need for displaying strikes, banning non-payers etc.

The current blocking system relies on sellers putting the non-payer block in place.  Many sellers, especially new sellers, are unaware of the blocks.

On the Sell Your Item page, instead of having a section that lets you choose to block those members with more than 1 strike, you have it that it automatically blocks those with more than 1 strike in the last 12 months.  Then, as you list, you get the option of:

- disabling the block,

- modifying the block to more than 1 in 6 months, or

- modifying the block to more than 1 in 1 month.

Sellers would still need to go through the UnPaid Item system when they have a non-payer, but, repeat non-payers with strikes would be blocked from every seller that leaves the block in place, and those that disable the block - well they have no grounds for complaining about non-payers.