Why not? It would be absolutely different. And if we had 50 nobles, we would own your infantry only army. Even with half the nobles you have we do some pretty substantial damage relative to what would be done if you all used normal army compositions. Now, maybe you would wise up and start using archers if we had 50 nobles. But if we kept the same army compositions, and had similar activity rates (big IF there), we would win most every battle.
We don't field an Infantry only army, we have a large and powerful ranged Special Forces contingent, and very limited archers. But, I don't think you would win on a strategic level, Madina even with nearly three times as many nobles as Aurvandil had, when Aurvandil was starving and down to three regions couldn't beat us. Even after they got support from the Caerwyn nobles and the Grand Duchy of Fissoa they still couldn't beat us. Aurvandil grew up fighting realms with more nobles, more gold, better recruitment centres and stronger economies well supported by allies, whilst having none of those ourselves. Thus, the core Orvandeaux leadership are the kings of getting by on nothing and going far with very little, we can put ourselves in a situation where we are out gunned and be confident of victory. Which is why I find it hard to believe that Terran would be able to match us even if you had the same number of nobles, Aurvandil's strength has never been in its numbers, never. But our strength allowed us to bring forth large forces over time. Plus, no realm I have seen has the same stomach Aurvandil does for extremely bloody wars, back in the day every two-three weeks or so we'd lead 2500 men on a suicide mission on Tower Fatmilak just to force Madina to keep spending gold on fortifications and to stop them from taking the fight to us. If it comes to it we can just grind our faces against your sword long enough for it to snap, or the moment it shows any weakness we'll exploit in it an instant, Aurvandil is powerful because we pick our battles, we only fight when we know for sure it will complete an objective, and we are powerful because we always go for the kill immediately. No foreplay, as Barca and D'Hara learnt the hard way in Rettleville and Paisly.
People make the mistake of assuming we simply overwhelm our opponents, when it's a case of we choose battles we know we can win, or that in defeat we will come out better strategically. Which is what I was advising Glaumring to do in Asylon, since he seemed stuck in the mindset of fighting battles when you aren't sure you can win, just because the enemy army is there, same with Terran actually, against us and Kabrinskia. Which is what Summerdale did in the north as well.
Am I trying to square up to you? I don't really know what you mean. But that comment was direct at Glaumring and how dumb his reasoning was. I get he doesn't like Astrum for one reason or another, but likes Aurvandil. It simply doesn't make sense that that reason would be "Astrum is big" because Aurvandil is a lot bigger.
Squaring up is when you stand ridiculously close to some one, square your shoulders and pick a fight, usually by shouting something obnoxious like "Yeah what" in their face. Which just seemed like what you were doing.
Glaumring likes Aurvandil because we conquer, but we then hand that land out on a whim for people to do with as they please, create what they like without interference. We don't just hold onto it, or give it to people we know will be our allies and support us. Hell, Aurvandil will likely end up fighting Falkirk, or the new Paisly realm if we ever end up in peace time.
The Astrocracies don't set up free realms? Just because they are mostly allied with each other doesn't mean they aren't "free." They all do basically whatever they want individually.
Well, I mean "not free" as in they are set up and are instantly just apart of the Astocratic federation, it makes little difference if they're a new realm or in their old one, they're still friends with the same people, subservient to the same goals, and thus, not free to pursue a completely independent path, whether they want to or not. That, and I am always under the assumption that the new realms in the north are only ever set up on the condition that they do ally, and that they are subservient to the dominant religion, and do maintain the peace. Whereas in Aurvandil, you could openly declare to Mendicant that you would fight a war with him and he'd just say "Come back when you're big enough for me to feel it" and still hand you a mandate for a new realm. With Madina City Mendicant literally just said "Who wants a new realm" then picked whoever was more convenient at the time and let them create whatever they wanted without Mendicant giving any input or conditions whatsoever. With Paisly he pretty much handed it to Florence because she was the former ruler of Madina, a woman, and too licentious to attend his banquets with any decorum, and he said "Do whatever you want so long as you do it fast and I don't have to pay for it". Anyone in Aurvandil can make a new realm of their choosing since Mendicant basically picks them on a whim, if Aurvandil ends up conquering a city it's almost guaranteed Mendicant is going to mandate a noble to make a new realm and to do it before it becomes inconvenient to him.
You.. conquer... defensively? 
Take Paisland for example, we only ever conquered into it after Terran took it, before that the unwritten agreement with D'Hara was "We'll drop our intent for Paisly so long as you take it and keep the peace". The same with Madina, Mendicant was desperate to get Madina to sign peace so he didn't have to go through the inconvenience of peace by conquest, Mendicant doesn't want conquest, he's too lazy for that, he just wants his opponents to submit as though it were a duel to surrender, a mutual admittance of who was the better swordsman now lets leave it at that.
We conquer as a reaction, to defend the Commonwealth. It's the same reason why we never conquered Rettleville when it was undefended after the battles in Maeotis and Paisly, Barca no longer presented a threat so there was no need for it as a means to defend the borders of the Commonwealth.
