While the concept has many many flaws I think it could potentially be made workable-ish.
First of all your choice of armor is not exactly good for melee combat, as the ceramic scales would simply shatter and provide minimal protective value.
However that being said a chainmail hauberk is a good choice of armor, but not really maybe what you would want for your troops.
My suggestion for armor would be a jack of plate or a brigandine. As it would not only require less technical expertise to manufacture than maille, it would be much cheaper and more suited to mass production than plate. It also would be much easier to wear. And when worn in conjunction with padding such as a gambeson it would provide some of the best protection you can get short of full plate while still retaining a lot of your flexibility. It also doesn't rattle around like chain or plate and it's fabric backing would keep it from making noises so you could potentially be stealthy as well.
This armor also generally could be taken off and on on your own accord so your men wouldn't need squires or anything too crazy.
Pair this with some steel gauntlets and a nice helm and you'll be protected enough to shrug off most of what the medieval world can throw at you.
Now a little known fact about medieval warfare is that especially into the late medieval period and early renaissance knights were so heavily armored there were few ways to adequately kill them. However the most common was to grapple them and jam a knife between their armor joints or into the faceplate.
Your men could perhaps if their gauntlets had long enough spikes employ that tactic in close melee to subdue even the most formidable armored foe.
However, getting close enough to deal with your enemy in melee is the problem. And you would need to force your enemy to close with you in chaotic melee for this type of combat to work.
These hypothetical unarmed soldiers would have three major challenges to contend with.
The first is missile weapons. Archers, slingers, crossbowmen. Now if you changed your shields to become larger kite shields you could create a sort of "testudo" formation in which you pack your troops tightly behind locked shields to shrug off all but the fiercest arrow volleys till you reached melee range.
Of course this defense isn't foolproof and you might take some losses but it would allow your unit to close the distance without being slaughtered.
However, your men are also wearing armor with the equivalent protective value of plate, but just slightly less. So your men, like armored knights could shrug off all but the most withering arrow volleys. You would end up losing more men this way, but only an unlucky dozen that got an arrow through the eyepiece or a gap in the plate, and the rest of them would end up looking like porcupines from the arrows stuck in their armor but you could close the distance. Now keep in mind this only works if you are using steel plates in your brigandine, softer iron plates would be easily perforated by the arrows and they would drop like flies.
The next challenge they would need to contend with is cavalry, which honestly there isn't any good answer for. The kinetic energy of a charging knight on horseback is too much for all but the strongest armor to handle. The horses also have a huge mass advantage that would allow the horses to simply barrel through your formation and scatter your troops.
Even if you had bigger shields they would eventually break through as you have no way to neutralize the advantage of enemy horses.
The best I could offer you is train your men to grab the lances somehow and yank the knight off horseback mid-charge and then grapple them and stab them through their armor with gauntlet spikes. However unless your men are near-superhuman that would be next to impossible. Just because you don't have nearly enough leverage to do that and would most likely get dragged by the horse. A smart knight could simply just have his horse rear up and kick you over and over with its hooves knocking you on your ass and trampling you if you tried it. To even attempt this you'd need a lot of space to maneuver so it wouldn't go well for your formation. But if you made it somehow possible it's your only option.
However that assumes heavy cavalry, the kind that does charge into melee. Light cavalry would simply swoop in and pelt you with arrows and javelins and then retreat before you can catch them. They would also glad you into chasing them and tiring yourselves out, breaking up your formation and charging you. So your men would eventually start dying as they would slowly nibble away at your forces. However, due to your pretty protective armor they might run out if ammo before they attrit enough if your men to shatter your force. However the light cavalry would just play with you at their leisure and since you don't have pikes they can also attempt to trample your men with their horses. However, they are much less armored and equipped so you'd stand a far better chance than you would against heavy cavalry.
So against any form of cavalry your form of combat is nigh useless, which puts you in a dilemma.
Now your biggest and most important threat is the enemy shield wall. These are a forest of spears wielded by either professional mercenaries or peasant conscripts. Making your armor styled after fearsome creatures could work as a psychological factor to intimidate your enemy. However even then it is doubtful if you could simply wade your way through spear points no matter how good the armor, and even if you did they'd drop the spears and pull out their swords, axes, and maces to fight you.
So this makes this form of combat workable in only one scenario. You would have to fight them in the woodlands or other difficult terrain where the enemy us unable to assemble huge formations or maneuver huge spears, or even cavalry troops, allowing you to fight lighter armored and armed foes that are all dismounted. And provided you have the armor, you might be able to just barely beat them off.
However this only works if your city or whatever is surrounded by huge dense forest with few ways in or out except for some main roads which can be impassably blocked. Of course the invading army could just burn the forest but in their wake but they'd risk accidentally burning themselves if the wind goes wrong. They could try and cut through the forest with axes, but your forces could ambush them there.
However societally that doesn't make sense as your people are farmers and would need that land for grain. So, that's the only way outside of guerrilla warfare you could make em useful.