Fallout Shelter: Recover from bad start?

Note: I think this question may be too broad, as there is a lot of theorycrafting that I've seen go into sustaining a fort; as such this answer will be used only as a means to help the OP dig out of a hole

Do not start making babies too early in the game.

Once a baby is born, they start to consume resources. If you have too many babies, then they're all sucking up resources, and not able to actually contribute to resource generation.

My vault consists of

• 24 dwellers
• 1 fully upgraded 3-wide power generator
• 1 fully upgraded 2-wide power generator
• 1 fully upgraded 3-wide kitchen
• 1 never upgraded 3-wide water treatment plant
• 1 never upgraded 1-wide Stimpack producing room
• 1 never upgraded 1-wide Radaway producing room

I'm currently sitting at about 24,000 bottlecaps, and have been playing consistently for about a week.

It seems like we're pretty similar in terms of setup, so I'll try to put as many things as possible that I've done to get here.

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1. Basics come first. Stimpacks and Radaways are supplemental. If you don't consistently have excess power, water, or food, focus on those until you do.
2. Of the basics, Power comes first. It doesn't matter much if you have a legendary dweller with 10 Perception, if there's not enough power to keep the water treatment plant on.
3. Water is more important than food. Any excess food (ie. past the vertical line on the food meter) will be used to heal dwellers slowly over time. Any excess water will be used to reduce the amount of radiation dwellers have over time. Sure, excess food is good, but if your dweller's health is capped at 50% because their rads are so high, then they can only ever have 50% health. Food will not remove rads, water will not sate your dwellers.
4. Rads affect happiness. The more irradiated your dwellers are, the less happy they will be. I've seen happiness drop rapidly from 87% to 10% when power to the water treatment plant was cut.
5. Put the best people into the best positions. I know, this may seem basic, but it really does help. Even if that means it might not be the most efficient. For example, if you have a dweller with 2 Perception and 10 Intelligence, and you're having water issues, move them to the water treatment plant if there's room.
6. The more upgraded a room is, the power it will consume. Rooms without dwellers in them will still consume power.
7. Don't be afraid to remove rooms. If you're having problems with power, remove rooms that aren't critical. You don't really need a radio station if your dwellers are starving. You'll have more opportunities to get those caps back once everything is under control.
8. Only upgrade and expand rooms when you have the time, space, and resources. Sure, a fully upgraded 3-wide power generator will produce a lot more power than a non-upgraded 1-wide power generator. But when incidents happen, they will be based more on the room, and not the dwellers in the room. So an incident in a fully upgraded 3-wide generator will typically be worse/harder to complete before spreading, than a 1-wide non-upgraded generator will. As such, if you have 4 dwellers in a 3-wide generator, they will have a harder time dealing with incidents than if they were in a 2-wide generator (where the max number of dwellers for a 2-wide room is 4, 2 per room).
9. Prefer making babies to the radio for population increase. The radio has a chance to summon Deathclaws, and if you thought raiders were tough to beat when you're starving and irradiated, oh boy.
10. Only make babies when you need them. Food and water take a hit every time you make a baby. I would recommend only making babies once your existing rooms are fully staffed, fully upgraded, and you're consistently in the excess zone.
11. The line on the resources (as mentioned before) is the line at which you start to have a surplus. If that line is farther left, then your needs are low, and your generation are high. If the line is farther right, then your needs are starting to approach your capacity. Try to have more generation when you can afford it, because if your line is way to the right, and you miss collecting those resources once, you could quickly find yourself in the red.