Mixed armies are not nearly as effective as armies consisting of a single unit. They're arguably more fun to use, but most of the time you don't even have time to set them up before the enemy is in your face. Huscarls pale in comparison to Swadian Knights though. The first disadvantage they have is map speed because they are an unmounted unit which means you can have far fewer of them in your party if you want to catch anything as opposed to knights. Second, as infantry units they have no shock power whatsoever. A swadian knight charge literally sends any enemy line flying and separated (yes, even lines of spearmen). With huscarls, their line is intact when the fighting starts and several enemies can easily gang up on a lone huscarl, both because their formation wasn't broken and because they're nowhere near as fast as a mounted knight. Third, they aren't as heavily armored, nor do they have a warhorse to soak most of the damage. They do however tend to do a little more damage over time, but this is negated by the fact that the initial charge of the knights easily wipes 10-15 points of hp away in charge damage from most of the enemies, and the fact that as stated before you can have many more of them before you slow to a crawl on the world map. The bottom line is, huscarls are good units and are better for sieges, but on the open field they are nothing compared to heavy knights.