I don't need to watch the whole replay, just first 1 hour to see how you set up your economy.
About defending first wave - move 10 axe fighters at position where I put them (I moved 20 there, but 10 should be enough), then move everything to the storehouse (after defeating enemy at top, remember about horses!). It should be easy with Scouts of second player, try to flank enemy to get rid of him faster. Don't waste your bows.
With remaining troops you should be able to get rid of enemy at east (thats what I always did when playing campaign). Take him one troop after another, from top, destroy him carefully. If you do this, you have one problem less.
Make up to 16 builders and 20 serfs at start, after gold production set, make up to 50-60 serfs (not all at once, from time to time, accordingly with expanding base)
You did the right thing - one of you going for iron while second goes for leather, but you need to do it faster. Check out replay (I was tight on food, so maybe another Farm would be a good idea, as well as another Mill and Bakery).
There's no need to build second storehouse almost never. You should block all wares in your starting storehouse at one point anyway.
4 Quarries is a must imo. Even 5 to build faster (stone is pretty far). I suggest iron player to go at stone at north east. Trade tree chunks for stone if necessary, then trade tree chunks for coal and/or gold ore.
Stone is priority on this map at start, but as you can see I went for wood (as you on replay) right away. Early farms would speed up your leather and food production.
Dividing wares - I set wood at 4 for weapon makers, 2 for Armor. Corn at 5 for Stable and Swine, 2 for Mill (however, try 3, should be better). Coal at 4 for everything should be good. Most efficent building rations: 2 Cutters - 1 Sawmill. 1 Sawmill - 1 Weapon Workshop. 3 Farms - 2 swine farms. 2 Farms - 1 Stable. About coal mines, you need one mine for each building that needs coal +1. 2 schools should be enough. As well as 2 Metallurgist's. On this replay I made only one Inn, but 2 would be better. Remember to put Butcher close to Inn, so he can eat fast and make more sausages
.
About attacking. I'd take green one first (after enemy on east is defeated ofc) by luring him at towers (with some army to defend of course), then focus on last enemy (he's really hard with all that iron...).
I would also make up to 30-40 Crossbows and make some pikes and always have some Scouts to flank the enemy. Make Axe Fighters and Bows over Lances (they are useful against horses, but not worth spamming).
I also attach my replay from TPR06 in campaign, when I was testing it
. Economy could be better, but maybe you will find some attacks useful, also where to attack and where to defend.
Hope it helps!