This depends on the faction,but if my pikemen aren't expensive (and most of the time,they aren't),I like to set their recruitment to infinite as soon as I get a decent economy.
The real problem with BoBo is that he is even worse at economy that me,he needs to work on it a bit.
A few rubbish tricks by me,mostly related to early game:
If you research the mill upgrade at the start (as soon as you build a mill,the upgrade in the mill itself),and do the blacksmith one early on,with 6-9 (try to increase it to 12-15 a bit later,and keep incerasing until you have some 20-25,that is the max number before they start bumping into each other I think) peasants you can have a really nice food income. True,some of your peasants may die early on if you aren't fast,but fuck it,the food gain is massive.
Getting a secound town hall is IMPERATIVE (after a barracks and a academy,ofc,preferably at the same time when you get a academy) . But,as soon (or before) you build a secound town hall,build a mill or two and plant wheat,and then when the hall is built start building moar peasants and telling them to gather it all. This is especially important for Ukraine or Poland,I think,but every faction benefits from it a lot.
I actually try to get a third and a fourth town hall,but a similar procedure follows.
With your town hall selected,you can right click on a spot on a map to set a gathering point. Pretty basic stuff,but if you set it on wheat/wood/stone,the peasants who you recruit will automatically go and gather that shit. Less annoying micromanagement and faster economy.
KEEP RECRUITING PEASANTS,and sending them to build mines/gather food/wood/stone. You have to keep doing this.
The academy upgrades are very good,but there are a few who you really,really need. The wood and the stone one,for example. They basically give you a double gathering rate. But the second stone upgrade is REALLY wonderful - 300% of the basic gathering rate. So,you should increase the number of stone gathering peasants to around 30-40 when you do the first upgrade,then try to get to the second one fast,and then get around 90-150 peasants to gather stone. Why?
Because you then get massive amounts of stone that you can use in building,but much more importantly,trade for other resources. This is life saving and enables you to get many,many upgrades much,MUCH faster.
Thanks to my luv and guardian Angel Mukaka Popo for telling me about dis great trick.
Oh,and PROTIP: When you get a market,press CTRL + 1 to hotkey it. Then every time you press 1 you can bring it up without the need to find the damn thing in your town. Much faster,much more comfortable,and much better. You can do the same with units and other buildings too.
I am not sure how good it is to get light infantry,because they are ultra shitty (I love the Mercinary Dragoons more,30 of them can raid by themselves quite well early on,but they are quite expensive),but mercenaries are really essential if you are about to get rushed.