I played around a bit, comparing them to other assaults.
2 Knight vs 4 thug (even metal): The thugs get completely kited, and do basically no damage, if the knights keep at max range. The thug IS faster, but not so much faster that they can catch up. That said, the knights have to run away. Ingame the thugs would get to avoid this engagement. If the knights don't run(but still dodge), then the thugs manage to kill one and do ~80% damage to the other before all dying. Knights can dodge the thug's gun, so the outcome is highly variable. But who fields thugs alone? A single rogue, or even an outlaw for the slow, makes this a totally different engagement. Since the thugs get to pick their fights (speed advantage), they could also retreat to recharge shields after a few shots.
5 knights vs 2 minotaur(50 metal advantage to knights): Minotaur can kite them and suffer barely any damage, while killing them quite quickly. Brief periods of disengagement to let the stun go down, and juggling which tank is exposed improves the outcome. In an outright slugfest(Read: tanks being controlled by an idiot), the minotaurs still win with one tank at half health so long as two knights are killed before one of the tanks is stunlocked. If one tank gets stunlocked up front, the knights win barely. Knights can dodge some shots.
3 knights vs 4 ravagers(50 metal advantage to knights): Lose one ravager maybe, killing all knights. The ravager can actually kite the knights if the knights are giving chase. Ravagers also have the range and flexibility to only expose themselves to one knight at a time, since they basically have the same range. Best move for the knights is to absolutely avoid chasing the ravagers, and make sure to quickly form a line to the current positions of the ravagers, to have the best chance of landing hits. In a straight charge and slugfest, lose two ravagers to kill all knights. This can be improved with a silly tactic: Charge dead into the knights, and push/drag one of them away from the others, until you are out of range of the other two. Kill it, then repeat to separate the last two. This tactic usually only loses one ravager.
2 knights vs 4 hermits(*100* metal advantage to knights): ON FLAT TERRAIN, the hermits completely kite the knights, suffering no damage. If you do the absolutely dumbest thing ever and charge directly into the knights, you lose 2 hermits and still kill the knights. This one surprised me the most: Hermit is faster, has more range, more dps for cost, is all terrain, and benefits massively from elevated positions.
2 knights vs 3 halberds(40 metal advantage to knights): Halberds win with one remaining. They take very little damage or stun until in range, then very quickly annihilate the knights. They still suffer a bit of stun, but can confidently win this engagement every time. Can also benefit from pushing the knights apart, like ravagers.
6 knights vs 7 blitz(even metal): The knight is favored a little. I can consistently micro the blitzes to kill 3 knights, while losing 3 blitzes, then escape. There is accumulated EMP and damage that needs repaired at that point, while the other knights are unharmed. Staying results in one more dead knight, and losing all blitzes. That said, the blitzes are able to retreat effectively and get those repairs; if they did so and returned, 4 blitzes can kill the remaining knights without losses. Good micro for the blitzes would be avoiding shots from the knights when approaching, mobbing a single knight, and making sure to hide behind whatever knight you are shooting; since the knights can't shoot past eachother. Pushing knights apart is also still effective. Notably, the blitzes almost always stun one knight before they suffer a stun themselves. Good micro for the nights is singling out a blitz for dead, and making sure that they can all fire.
Some other engagements:
*Jacks are too slow, so have a hard time catching more than one knight.
*Pyros are terrible vs knights, because they get stunned by a single shot, have low alpha, and are easy to hit.
*Knights can stun a jugglenaught if it's being controlled by an idiot. Otherwise, it can pick them apart. Even Jugglenaut outruns knights, without jumping.
*They can kill any striders they close range with, for cost, except detriment. This means they can slow strider advances, in larger numbers. They are not fast enough compared to striders to catch them in the open field though, assuming the strider retreats into friendly lines. But using striders totally unsupported is idiocy.
(Before you think that they counter jumpy: They are useless against a firewalker, or moderators.)
* They kite reavers, and stun in a single hit.
* They are evenly matched against rippers, if they spread to not die to AOE
* They aren't terrible against all raiders. This doesn't make them good, but they tend to be able to fight off lesser-metal groups of raiders on their own. For even metal, low cost raiders always win. Mid-high cost raiders are a mixed bag.
* Scythe does very well against them
* They
can tank licho bombs, but take a lot of damage. Since they are lowish cost (so you need more than a few), they are actually quite vulnerable to fire bombs or firewalkers.
* They are slower than shield balls(even without lob meta), so their extra damage against shields is sorta moot.
All of these engagements are, frankly, unrealistic. Their slow speed makes them
the most hardcountered by skirmishers of any assault. If my enemy starts using knights, I'll start making some skirmishers to mix in.
As a general statement, being more effective when cloaked is in no way unique to the units in the cloaky factory. Being slow so it's necessary to stay cloaked isn't an advantage.
As of right now, I really don't think that they have anything good that compensates for their abyssmal speed. They don't get better range, dps, or health. They are hardcountered by literally anything that outranges them, including other assaults. They have the second worse movetype in the game, and are dramatically affected by non-flat terrain anyway, so really want to be on flat ground.
Being immune to emp would be a very strong synergy with the imp. As of right now, putting the knight close enough to act after an imp makes then extremely vulnerable to just having the imp get them killed. That said
Another thought I had: What if the lightning gun emp arced to nearby enemies? Only the emp effect, not damage. Possibly only arcing to units that are already stunned or already have stun above a certain %. That doesn't increase their damage output, but does make protracted engagements with them more dangerous.
I uhh, totally didn't waste my entire morning doing all this.