Yep. Everyone says 'HP protects you against one round deaths' but AC arguably does so even more effectively. Going from 40% max hits to 30% max hits reduces your chance of being quadded for max from 0.4^4 = 2.5% to 0.3^4 = .8%. That's very significant, because it's those max quads that break your CH chain.
Also, remember that +HP really isn't that effective on a warrior. If you have 6000 HP, then +100 increases your total durability by 1.7%. If 1 AC is worth say 2-3 HP, then 100 raw item AC (not displayed AC) should reduce damage by 5% or so, and that requires parses of thousands of hits. Also, bosses have higher ATK and thus require more AC.
TLDR: I stacked AC on Sakuragi over HP and I don't regret it. If I were more into raiding, I'd be going for something like
Alde's build except with a Palladius' Axe, Orb of the Deep Sea, and Ring of Destruction.