Yes, you can put pages of different templates within the same folder and create a media pool like single folder. There are two issues with this approach both depending on the amount of pages.
- given a bigger number of pages Kirby will start to slow down. at about 1000 i would say. at about 5000 pages you should definitely add some caching around aggregated list (like top 5 posts of a category etc).
- if you allow manual sorting prepending a page will cause the directories of all pages after that to be renamed. depending in the amount of pages this might slow down the panel for that single action noticeably. you can avoid that if you set the
numto use a date field to sort chronologically.