A quick google about planting basil might give you the answers, although there seems to be a lot of conflicting opinion-guess it depends on the size of the pot, the type of basil, how close the plants are, how much and often you'll feed them, etc.
My experience is limited- I grow only bush basil types and tend to give them at least 10" to themselves so they're not crowded, but they might be happy with less space. I'm not familiar with all the types you are growing. I wait until they're sturdy enough and have a couple sets of true leaves before I transplant, but I've never grown so many together in the same cell as you show, as I only need a few plants.
Wish I could be more help- think you'll have to hope for a basil expert, although there appears to be a lot on-line about how to grow basil while you wait for another response.
Hope you have better luck with it this year...that's a LOT of basil!
