In that case I would personally just set the new category as "no ruler designer". That replicates the conditions of the 1.1.3 runs and it's simple and straightforward.

I agree. At this point it's pretty much 100% down to RNG using the Irish King of England to get the lowest times and I can't see any alternative strategy being able to compete.

Personally rather than these I would split into any% and a "must start in Ireland" category. The ruler designer allows for more diversity of strategies and so long as the character has to be or replace one of the historical characters in Ireland you can't go too crazy with it (I tried, lol).

A lot of the brokenness of the current strat comes from being able to start at king tier and with much larger levies than any Irish ruler, you can remove that by requiring a start in Ireland without having to ban the ruler designer.

That said if I had to pick between those two options I would go #1 personally, simply because I think it's better to keep to the minimum number of restrictions possible to define the new category.