Auto-translated
I really enjoy playing as Haven, so I also love their magic.
Firstly, it helps reduce losses on neutral creatures, which is especially important on large maps where Life magic truly shines. Secondly, the Haven army itself is very strong: Squire with stunning, Archer without penalties, a solid melee unit that also doesn't retaliate (I don't use the Ballista), Monk is decent, but with accuracy and developed Life magic, it turns into a monster. The Crusader is strong even without magic, but with magic, it's simply overpowered. The Champion is good, especially with buffs (especially with Guardian Angel and Blessing). However, the Angel is more useful because it can resurrect and, most importantly, it's very mobile, while the Haven army is unfortunately slow, but the Sanctuary can help with that.
But the most important thing is, of course, the artifact. If you get the right MASS artifact, you can consider the game already won.