[quote=@KatherinWinter]
Nyla might make that growth harder.
[/quote]
How so? Unless you have an issue with the story dragging a little longer to allow roleplaying time for an extra character. From the way I see it, this character could expose the current PCs to new situations and provide them with opportunities for development. I'd personally welcome a new character/player which is why I offered to help with the introduction. I also foresee the interactions being quite enjoyable. Well, it's ultimately up to you whether to accept her or not.

[quote=@KatherinWinter]
I also want them to bond as a group which is already a challenge.
[/quote]
It's only a matter of time before they do. Now that we understand that this is the direction you plan on us moving in, we can ease up on the random ambushes to give time for interactions/breaks.