They do beat every single archer in the game at melee fighting though, being able to stand up to most T3 infantry. However they usually get outdone in field battles by both Vaegir and Sarranid archers due to rate of fire alone. Rhodok's clearly is the worst faction, but their sharpshooters are the best ranged unit in the game at taking out armored enemies. Swadian Sharpshooters are admittedly not that impressive in field battles, but are second to Rhodok Sharpshooters in terms of defending against a siege, however in this case it's a pretty big gap, and both the Vaegir and Sarranid archer's are still situationally better choices depending on the castle in question. Swadian Sergeants usually beat Rhodok Sergeants but are less effective defensively, and are overall probably the second strongest infantry unit in the game. In fact Swadian Knights are probably the best unit in the game period, even dismounted they are only beaten by a few units. Swadian Knights are the best calvarly in the game, but Sarranid Mamelukes are ALMOST their equal. The closest thing they have to a balancing factor is their early tier units are much worse than other faction's early tier units, but that doesn't matter since they overall have some of the best high tier units. I've got enough hours in this game that I can confidently say that the factions aren't very balanced, but each of them is at least playable. Distracting part of their force myself can also split their forces and prevent a push back from attrition. Then there is no need for mulitple sieges because the sharpshooters will take care of their reinforcements as they spawn in.

I will have some sharpshooters lower down the list so they show up with reinforcements and shoot down into the courtyard.

Together they can easily gain a foothold on the wall. Personally I usually don't have patience for that so I often just bring along a small number of Nord Huscarls and companions to lead the way and follow up with Rhodok Sergreants. Order your crossbowmen to spread out to reduce losses and keep any other troops in the rear Using this tactic 80 troops can take out 400 unless they have a lot of elite archers themselves or they sally out to meet your assault. Repeat until you grind down the enemy defenses to a mangaeable size for your infantry. Camp ouside the wall with sharpshooters until they run out of bolts then withdraw and return with a replenished supply of bolts. If you want to wear down a castle's defenses with multiple assaults using Rhodoks, use the crossbowmen.

Mount and blade rome at war