Adult females are always good to have, I have only let one of mine go since I started breeding over 4 years ago--and that was due to her bad temperament. I see no reason to sell normal breeder females, unless there's an issue with space. They still produce 50% co-doms every year. This year, a bunch are going with a double co-dom male, and I'll be getting some double co-doms out them.
Hatchling normals are easy to sell in some areas, and less easy in others. Always remember that people are willing to pay for what you have put time and care into, if you present it properly. Out of around 100 hatchlngs I produced this year, I had probably 20 normals, and I have 1 left, the rest have already sold. Keep good records, and treat them as individuals--pet seekers will buy them.
While there's little sense in raising normal females from hatchlings if they aren't exceptional, the same doesn't hold true for morph females. Their value increases sometimes 10-fold in the three years it takes them to reach maturity. Pastel hatchling females may sell for 150, but pastel adult females may be as much as 1K. Depreciation definitely doesn't account for all of that.
On the other hand, keep in mind that they are still mouths to feed. If you were to purchase a few adult females instead of 7 hatchling females, you would be able to make enough money to feed your collection, and all of your holdbacks, from your first few clutches. The year after that, you could simply buy the morph females you are interested in--possibly even low-end adult morph females, which saves you even more time, and gives you even more money to invest into the collection once they produce.
There's a lot to consider.