I had similar problems at the beginning.
Basically, it all boils down to this :
- The enemy AIs, even at the lowest difficulty levels, are very good at producing, maitaining, and moving around lots of troops quickly. Unless you are a very well experienced player, the computer will be better than you at producing masses of armies.
- The enemy AIs, even at the highest difficulty levels, are poor at planning long term (most glaring examples : building castles, build up, accumulate and keep alive elite troops to reach a critical mass when they are unstoppable vs. wasting too low amount of them in fodder armies) and building elite, balanced armies with appropriate and effective magic support. After the (admittedly quite hard) learning curve, you'll be able to outrank the computer in those domains, even if you are not a veteran or super experienced played
- It is easy to feel overwhelmed and pressured by the computer masses of agressive armies, and try to keep up in numbers instead of responding with quality. Which is a good way to lose
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I HIGHLY suggest at the beginning to play a large map with a lower number of opponents. It gives you a breathing rooms, relieves you of the pressure of having a fast expanding computer "rush" you, and allows you to build up superior armies.
With those 3 basic parameters in mind (easier said than done, admittedly
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), it will be maybe a bit easier to focus your strategies.
Some more precise elements :
- Among the most important factors when comparing "comparable units" (eg. "similar" buildable, moderately priced regular human infantry) are protection and morale. A heavy infantry unit with 15+ protection, all other things beeing equal, is VASTLY superior to a light infantry unit with 10 or less protection.
Especially against neutrals/independant provinces, battles are very rarely to the death, whoever rout first lose, and it is not necessarily the one who suffer from the most losses. Having priestly support to cast sermons of courage is fundamental (one of man's flaws, but cheap bards with the "standard" bonus, the song of morale and close to your combat units can do the job). Having the highest morale is vital.
As for your specific examples : Human Axemen and Spearmen are, frankly only barely ok (don't even think about militia). Tower Guards are your best bet if you need lots of cheap, build everywhere infantery : they have superior morale, decent protection, and a shield. Yes, they are a bit more expensive, but they have much more Lasting power.
Man's infantry is not their forte anyway, but you don't need elite, kickass infantry as man, you have great longbows to deal damage, knights to crush enemy's flanks, and great "special" units (wardens and knights of avalon) when/if you can afford them. All you need is a not too costly decent infantry with OK standing power (= both protection and morale) to serve as meatshield, and tower guards are imho you best bet.
Thought their strategic movement of 1 bites ... Keep your eyes open for better independant infantry (you can find some with 15 protection).
Anyway, don't invest too much in infantry if you are man, your power lies elsewhere.
- At least in the beginning and in single player games (there are always way to counter specific troops and tactics, so don't put your eggs in the same basket in multiplayer), buy lots of longbowmen. They are relatively cheap, and immensely powerful against almost anything independant (except the strongest provinces), and can hold their own against many AI armies. Divide them in 2 or more Groups instead of a big lump, put them slightly behind front ranks, on the flanks (to avoid friendly fire).
When/if feasible, try to boost them with magic (as other suggested, wind guide is excellent, but "gem logisitics" is pretty hard at the beginning).
- Try to build up (even if they are damn expensive and slow to produce) a force of elite shock troops : knights (and knights of avalon) and/or wardens. Those will win you the advanced battles. You need however to commit yourself to producing a critical mass of them (sending them piecemeal to the opponent with only fodder troops as support is a very bad idea), and strike a balance between accumulating a good amount of them, and produce cheaper troops to expand and respond to the computer's agressiveness.
Fortunately, as man, you have cheap AND effective units with the longbowmen. Cherish them
- Magic support can turn the tide of the battle, even if it is a hard learning curve too, choosing the right spells and avoiding the intial pitfalls and disappointments (friggin' mages can't hit the broad side of a barn with their attack spells). Man's mages have quite a lot of straightforward, useful, low level spells : try tangle vines, sleep, aim and lightning bolt for starters.
And it is not limited to combat magic, summoned creatures can beef up armies enormously, and are a great way to avoid beeing overwhelmed by the opponent. Gold and ressources are hard to come by, you always need more to build troops ... gems are an ADDITIONAL currency usable to "buy" more units.
As other said : expand quickly.
And a little note : although man is a very "familiar" theme with easily recognizable units, it is maybe not necessarily the more comprehensive faction to start with (a nation combining powerful magic and mediocre infantry and priestly support is harder to play than the opposite at first).
Many players usually suggest base Ulm (although the sheer number of different kind sof infantry is intimidating at first, I think in the very beginning you can pretty much build any of them indifferently, and make more educated choices later when you are more familiar with the game) : arguably the best infantry in the game, insanely powerful (though expensive) knights and powerful crossbows. The best and easiest to understand combined army of regular troops. Aside from that, you have poor priest and specialized mages, not bad in their field of expertise, but very specialized, so you don't need to have lots of experience and understanding of the intricacies of magic to play Ulm well. Just rely on the standard, intuitive, "real life"/historical basic troops tactics.