That wouldn’t change anything imo. As you said xbows and Knights live by their respective powerspikes. Knights need almost no upgrades. For xbows you usually have a bunch of archers lefover from feudal.
Both units are excellent in dealing economy damage , especially raiding.
A 2HS upgrade in castle age alone would require you to first have enough LS leftover to upgrade, otherwise you lose the timing. And then you would be lef with a bunch of 2HS which can’t even raid as they are slow and frail, die to any TC fire super easily.
What would be necessary to make the militia line play a generally bigger role would be to bring all ubrgades except the champion down one age. The MAA could be either a bit weker in Dark Age (and automatically improved once reaching feudal) or be a bit more expensive when they turn out to be a bit too strong there,
The other upgrades of LS and 2HS could potentially be made a bit cheaper to fitt the economies of the respective ages.
Here is an example of one of my own civ designs I tried to built up around that bonus:
I gave them access to all militia upgrades except champions one age earlier. I gave their skirms extra damage against archers so they actually can somewhat deal with the archer line of one age above. I gave the militia line a passive ressoruce trickle equivalent to about 1/5 vill, so there’s an encouragement of making the line early and upgrade them later. That’s imo better than something like a cost reduction to the upgrade, as it encourages to mass them earlier, not just on the way up. They also get the pikeman and halb upgrade one age earlier for the same reason as their skirms have extra damage output. Lastly they even get a tech that gives their foot units extra armor.
And even with all that I still question wether this will be enough. Or if we maybe just will see an 5 Maa rush in Dark age and then standard play with archers until the very lategame where their Champs can become very Powerful again.
LS actually already beat Knights in a “fair” fight. Issue ofc as the Knights can chose when to fight they will take it when it’s in their advantage.
The current meta is to use your military powerspikes to damage the opponent eco and then add eco behind that. And I just don’t see the current LS or 2HS really fitting in their, as they aren’t made to deal a lot of eco damage with few investment. Imo the high food cost isn’t even the problem anymore as in the current meta we usually get out of feudal with a really high farm count. meaning in early castle age we most of the time actually have enough food that could be used to make LS. Even on the way up. The issue is just that the unit doesn’t offers the thing we want at this stage, which is A) a military powerspike that’s very hard to deal with feudal units and B) just pure Raiding potential. And with very low investment as we want to transiotion to boom asap, to get the economic advantage.
As it is desctribed it will basically never be used, at least on any level above like 1k2 elo. It just doesn’t provide what you’re looking for in a unit at that stage.
That’s generally one big reason why I ask for adding a differen infantry unit instead. Champions are already associated with certain playstyles. Also the whole militia line (except for the MAA) doesn’t has any “iconic” thing with it that qualifies them to be seen more than once in a while. It would become very boring and then hated if the militia line would become one of the power units in the midgame. People would become angry just because they don’t want to see that line there.
The reputation of this line is already settled and I don’t see how this could be brough back.
Lastly the low gold ratio of the militia line plus having no trash counter actually disqualifies them already to become a “power unit”. Power units need to have high gold ratios so they aren’t “expendable”, to give an emphasis in caring about them an trying to keep them alive. Also the (semi-) trash counter is an important factor for a lot of reason. One of them is that the opponent should still at least have a chance to win without gold access.
And the current milita line is exacatly designed around actually not having a trash counter. Meaning it’s one nice tool you have to your disposal when you have still access to gold but the opponent doesn’t.
With all this, the Militia line just isn’t eligible for being a “Power Unit” in my opinion.