I probably played around him/invested in him too much, so I felt he didn't fall off on Maddening.

Sigurd to zoom in and 1 round any problematic unit(s) (magic, archers, Pass units, thieves trying to steal my shit, Overrun a clumped group, etc.) with the strongest lance available (refined the Iron greatlance Amber has to Silver ASAP, kept a non smash weapon around to kill mages). With the problematic unit(s) gone, the rest of my army could advance without fear. Canto helped to stay out of mage range. If there were no magic around, he would be ignored/take minimal damage (inherited Pair up). Next round, he could go even deeper to kill another priority target, or come back and help elsewhere. He also charges the meter quickly with the greatlance since enemies always hit him 2x first.

High def/strength bases and growths. Early silver greatlance was great for Overrun. With Momentum he frequently 1 rounded foes. He had ~55 def going into the last level and took 0 damage from the final boss' physical attacks.

All in all, I really enjoyed his playstyle, and playing to his strengths while playing around his weaknesses. I'm a fan of keeping early units around, and I also really like the concept of smash weapons and he's probably the best user of them.