In the new templates, I see only 3 advantages compared to the old ones:
1) a market has been added,
2) a sacrificial altar building has been added (although I would put it in the secondary templates, I don't remember if it's there or not),
3) phoenixes have been removed from a number of templates (although it would be better to solve the issue with their protection or move them to hard-to-reach places).
As for the disadvantages, the protection has been removed, especially from small artifacts and witch huts in the secondary templates. It generates too many skeletons (you can collect a good collection in the first week, which is clearly unnecessary). For example, in my game, 5 skeletons and 3 wagons were generated in the starting area, and not a single chest, but it's still playable if it weren't for the bugs with the mountains.