Here's what I've found:
Leadership is good for Moral at high levels and that's about it, it isn't useful for building army size once you are decently into a campaign. For example. I think I have about 30 troops from leadership and 260 from renown, you fight so much and gain so much renown that the leadership just pales in comparison. If I'm out picking fights I carry 140 or so knights with me, if I'm castle crashing it's 280 sergeants. Either way moral drops at such a rate that you have to keep fighting every 3-4 days just to stay above average(which means your gaining more renown). So that being said I wouldn't bother getting your leadership up past 5 or 6, it just isn't worth the massive commitment for charisma at the expense of so many other points and abilities that Int brings.
The most important thing for you as you move up higher and higher and fight bigger and bigger battles is not how many troops you personally can kill, it's a much bigger picture than that. First and foremost the most important thing for you is simply staying alive. If I am able to simple be on the field with my troops in battle I can take 150 knights and wipe out a force of 450 with loosing maybe 10-15 of them and having 30 or 40 knocked unconscious. If I'm knocked out and I have to order my troops to attack without me forget about it, I'd loose the whole 150 knights without making a big dent on the enemy. Hell 150vs150 and I'd be lucky to break even and win that one. So first thing is stay alive, put points into str and 4-5 into ironflesh. Sure get your leadership up to 4 or 5 to start so you can have some troops but after that build your ironflesh
Next you want to make money, god money becomes an important thing at mid-level, for this you'll want prisoner management and looting and trade. You want to adjust these as you level so they keep up with how much loot you're pulling and how many prisoners you're taking.. Spot the bottleneck and adjust based on that, so if on a regular basis you win a battle and you can capture 5 prisoners but there are 10-12 of them regularly available then add another point there. My sweet spot is 30 prisoners, more than that and it isn't worth the points(i'd rather get an extra 10% money from looting than the pesky 250 gold for prisoners)
If you're in open battle you shouldn't bother with worrying about anything on foot. It really doesn't make sense.. On heavy charger with a lance or sword you'll be inflicting 10 times more damage than you will ever on foot. I use the lance because of couched damage and the big speed bonus I get but the horse is really the most dangerous weapon you'll ever get. Consider this: when the battle first starts the enemy comes at you in a nice pretty line, I have the best heavy charger, insanely heavy armor and enough riding skill to gain speed. I can charge through an entire line of 50 troops with my shield down 2-3 times before my horse is low on health. I'm doing 5-20 points of damage to every enemy I run down just from charging and I'm hitting about 70% of them. The first run I'll do a total of 300+ hp of damage, the second time through maybe 200+ and another 200+ on the 3rd run. That's up to 700hp of dealt damage, there's simple nothing else in the game that can even come remotely close to dealing that amount of damage in that short of a time. Plus when I finally send in my troops the enemy are soo weakened that they drop like flies reducing the amount of fatalities my troops suffer.
If you're not on horse(sieging) stick with your bow and let your troops do the fighting. I can take out 7 bandits with my strong bow before they can even get to me(headshot, headshot, headshot), but in a siege it is even more critical. Again if you get knocked out you're troops are going to start dying in mass so staying alive is priority number one and you aren't going to do that with a sword on the front lines. But with a bow you can just put 3 quivers in your slots to have close to 100 arrows on hand and you should be doing headshots 30% of the time at least. That means you're going to do 1800-2200 hp of damage in a single siege but the best part is when you run out of arrows you just go pick some up off a dead forest bandit or archer and you're reloaded. All the while you let your shock troops get killed while you sit back and peg em off. Once you get good with a bow there's nothing that can compare to the amount of damage you can deal out in a fight without putting yourself in direct risk of getting knocked out, especially when you are defending.. Hell they just line up on the ladder trying to get through your shield wall and you just pop em off one after another after another.
Hope that helps, it's important to plan out your game for what it will become as apposed to simply reacting to what it is now, which it won't be for long
