-Broadsides: Outside of Kauyon, Broadsides make a big show of themselves; the often deploy centrally, drawing attention to themselves whilst maintaining a cover save. They attempt to abuse the enemy's fear of Railguns; making them target the 'Sides before anything else, leaving you time to maneuver away.
The downside of this is that the Broadsides are likely to be eaten alive unless thoroughly defended; in Mont'ka lists, small Broadside firebases are left in the dust, meaning the silencing of your railguns immediately.
In the Kauyon, however, they remain. Broadsides are often placed very far behind protective lines, leaving them among the last of your units to fall, only sacrificed to save Crisis Suits and your Fire Warriors. This means that opposed to a near maximum of three turns shooting, Broadsides can last 5 or 6, easily. This effectively doubles your anti-tank; something you can't see when just glancing at your list's weapons.
-Pathfinders: Regardless of the style, Pathfinders will receive the same treatment; newer players will ignore their non-damaging guns, only to be wiped by your buffed suits, while veterans will target them early and hit them with enough shots to send them packing... which is not a great many.
Pathfinders are constantly in danger in a good game. In the Mont'ka, the player must choose between setting them up in cover and camping until death, or continually redeploying them via transport to avoid enemy assaults. They either suffer the same problem as Broadsides, or they lose turns of firepower to stay around. Either way, they get in around 3 turns of shooting in MAX if they are under pressure.
In the Kauyon, they suffer the same problem; they are relatively easy to shoot out of the game. But the Kauyon offers a slightly better alternative to sticking them in area terrain or ferrying them; putting them behind a Kroot Wall. This may seem trivial, but it adds two major changes to the playing style of the pathies:
1) The Pathies get a choice of the best possible lane of fire. This is due to the fact that the Kroot wall can stretch to give them cover regardless of where they are. Instead of anchoring into terrain, they benefit from freedom and cover.
2) Assault protection. The Pathfinders no longer have to relocate to avoid assault; the Kroot have that covered. Without having to relocate, they avoid assault completely, allowing a focus on shooting; critical, as during the first few turns they have a large amount to support.
Why did I choose these two units specifically? Again the answer is two-fold:
1) They are the best of their role: They are the cheapest renditions of their incredibly useful and limited weapons. While others exist, they are inferior for that specific role; Hammerheads are inaccurate and expensive, while Stealth Marker Teams and Skyrays cost far too much for the 'lights they bring.
2) They work better in the Kauyon. These units both suffer from one drawback in comparison to their more expensive and less effective counterparts; they lack mobility. In the Mont'ka, this regulates them to an Alpha-strike followed by their inevitable demise. In the Kauyon, a solid system of blockading, trapping, and cover synergy leave them strong and firing.