The weakest castle in Heroes of Might and Magic IV!

Barbarians are strong on small maps, Chaos and Haven on medium maps (I haven't played much with Nature), and Necropolis on large maps (this is just a general observation, for example). But Life doesn't stand out anywhere, IMO.

It might not stand out, of course (but the issue isn't about the map size)... But in my opinion, this is a sign of stability. Life can adapt quite easily to any map and situation. That's a plus, whereas Death is really only very strong on a huge map thanks to its Necromancy. Although, again, it's debatable... Life (and Nature, and Haven, by the way) also benefits on large maps. Don't underestimate Resurrection (and especially Summoning).