I remember that the maximum number of item for collection, swap, wish, ignore is 400.000.
Since I am a member of Colnect that is the case, but since then the stamp catalog has increased massively and has now close to 1.5 million items.I think it was arround 800k items when I regsitered 10 years ago.
Both my wishlist and ignore list are almost at that maximum.
Regarding the unmarked list, I already try to use it in such a way that countries of no interest only pop up (Sharjah) , and also excluding the maximum number of emissions like cinderella, specimen etc
fore every stamp issued now, also full panes are posted, which was not the case 8 -10 years ago. And many countries are updated with these full panes. All going to my ignore list. I could maybe try to include that in my unmarked list.
But lately for the US, thousands of stamps are added with collectible margin / label almost each day.
This is the result of only a few days, I have already added thousands of items in the last couple of weeks. At this rate my ignore list of now 357k items will be not enough. And I have learned this will continue for a while.
this is something I cannot exclude as too many countries have attached labels/margins (all items from Israël, Belgium in the early 1900s) and the Netherlands will probably follow too as the stamps shown are without the tab, but they mostly have an intersesting margin.
My wishlist currently has 372k items. Each year I do add a good number to my collection, but soon it will be too small too as with the new issues they are more difficult to find.
So please concider increasing those lists, otherwise I will have to create a large number of personal custom lists with max 20k items.