Spear & shield bros forming basically phalanxes were a noob's crutch for me a long time before I figured out other ways to make it in the first few weeks.
Care to share a few tips?
I'm not the best BB player and no doubt folks here will have better tips. But I might as well stick my neck out so I can be corrected. (I tend to play Veteran, high starting income, semi-ironman.)
Spear & shield, again, is the bread and butter for any bro that isn't particularly great. And there's often an inflection point in terms of how many spearbros you need to maintain a decent front (all that Alexander the Great history I did back in the day coming into use). You can use weak spearbros down one side to encourage enemy to mob the other side with your best bro, for example (let's say, a gladiator with a two-handed weapon).
Because I don't use mods or reload a lot, I tend to build bros to survive early/mid-game rather than the optimal build for later. That can often mean taking some combination of Student, Gifted, Colossus, Rotation, Recover in the first levels for, say, unremarkable bros, to improve their survivability. Such bros may be abandoned later on, but that's when your company can easily afford new and cooler bros.
I am probably in the minority here but I'm a big fan of a couple of backline pitchfork bros in the early game too, because it's an easy way to deal significant melee damage to a focused target while maintaining a spearwall formation and can be viable for defensively useless bros.
Anyway, after a week or so with a few contracts done I'd phase out of that. As others mentioned flails are very nice mid-game, and get past the spearbros' limit of how slow they are in actually killing enemies. Axes I would say are the other to-go to smash up shields and get at the high-value targets. Not really convinced by cleavers / swords in general, while hammers arguably come into their own a little later.
I also tend to stick early game to a patch of the map that I know will be low risk - e.g. three or four closely connected towns that are easy to hop between and are not next to swamps or 'edges' of the map (where more threatening shit roams). On Veteran that usually means I have the luxury of bailing on a contract that will get me fucked. I'll usually focus on human bandit contracts first, like the thief one, and maybe some nachs & webknechts, while avoiding caravans or armoured undead. The arena now also offers a pretty good source of early money.