I'd suggest either the pikkolo or the baby hawk. THe babyhawk is quite high in the back - nearly everything is in comparison to the ergo, which is quite short in the body.

I have a kleinsmekker mei tai, which is absolutely fabbo.. but hard to get hold of. and uber expensive!!!!

I also have a beco butterfly II which is great, and sooo easy to put them on your back. and the back is quite supportive as well for younger ones.

I have a wrap too that I'm still learning how to put on.. LOL