Mostly agree, I think he is worse than you give him credit 
400% to one at Fast is weak, even vanilla Lianna hits harder. 450% at Average is even more of a joke.
Add to this the fact that Lasalle’s fiends are the weakest fiends in the game! Measly damage, very easy to remove at 12% healing, and no status effect.
Brilliant character that will make you feel bad if you pulled him.
Let’s look at the Fire HotM that have been released in the last few years:
Roughian & Nugrib was one of the best HotM ever released, and was much easier (cheaper) to pull. Much more usefull of a hero.
Tahir is a conditional sniper, which I am not fond of, but I would still level Tahir over Lasalle without a second thought.
Zagrog is Average speed which hurts him a little, but I honestly think I would rather use Zagrog on attack and defense over Lasalle.
Russell, okay Lasalle is definitely better here! Russell even at Fast would only be adequate. Sorry Russell fans.
Yang Mai, Lasalle wins another matchup! Yay Lasalle! 
Althought Yang Mai’s artwork totally stomps Lasalle’s!
Reuben, after he was buffed I use him frequently, he isn’t as good as many Fast-hit-3 heroes released since he came out but I would still use him over Lasalle. 260% damage to 3 is going to give me more traction tha 400% to 1, regardless of the fiend.
Noor, as much as I disliked her when she first released and despite the fact that I still think she should be Average speed (or maybe even Fast in this meta), she has a real purpose in this game where as Lasalle, less so. She is good for Rush and Minion Wars. She is good against minion heavy teams in Raids and elswhere. Lasalle has better stats and is Fast, but I think Noor has more use overall.
Jean-Francois I could go either way with. Against teams with a lot of defense ailments he is great, he also pairs well with Emilio, and is of course good against Ice heavy teams be it in Raid or Map or whatever. Honestly not sure if Lasalle is better (beyond stats)?
My opinion of course, but beyond stats is Lasalle a balanced hero? Nope!
So here are some of my solutions:
- Reduce his damage down from 400% to 300%, but make him hit Target and Nearby
- Keep him as is but make his fiend/s much stronger with 80% attack and 42% healing/health absorb
- Keep him as is but give his fiends a -44% to Defense ailment