Ye, the early game is pretty much all about keeping your gals alive and getting enough money to hire and maintain your brainers. You can kinda slow down when you get yourself around 10 brainers, in my experience (because you'll also need money for ammunition, vessels and materials to craft stuff). I dont think you really need a secondary base done by then, but its recommended that you do, just at least so you dont get a game over if you get trashed in a crackdown.
Anyway, the RNG can always screw you. In a past version I clearly remember being raided by the dark ones in the second year, hell baron and all, and only surviving by abusing good melee gals with tech blades.
A decent strat to deal with pretty much any crackdown other than the star gods themselves is to have a team of voodoo skilled gals with heartstopper staves. You can then scout the enemies around the base using dogs or other more disposable units and then smack them with wololo until they die. Its pretty good against merc crackdowns, which are otherwise pretty dificult, though you'll still need to take out the hovertank they'll inevitably bring, so you should always have anti armor and concussive damage weapons avaliable, the ones that don't need an arc to fire, at least.