My go-to goes like:
1. Unlock scale mail. You need to unlock cave hunting and do some of them to get chitin plates, then gather them as needed. 30 all around armor makes the life much easier.
2. Bounty hunting.
3. Shadowmasters for codex crafts. The easiest way to bruteforce them is to repeatedly research hoes, whom you can get like 5-6 per red lantern villa mission. So, second prison asap.
3a Airballs to arm a codex craft if you didn't get lucky. Though, most codices give some weapon and you usually can down a police car to get a gun.
I've checked my latest save and I see that my first crash site was done in May
4. Crazy Hannah. Aircraft weapon, mortars. (Around that time I like to get Rogue field warlords, love the ramjet cannon)
5. Interceptor by the end of the year to get into space
Strategy-wise I expand ASAP, because every new base at the very least means mess hall + sickbay, 2 more brainers. And radar coverage. With the amount of hunter killer enemies just checking by the graph becomes too dangerous.