As someone new to eventing with a green horse.... go with a more schooled horse. Not that I don't enjoy every aspect of my beast, but it would be nice if I didn't have to learn something first and then teach my horse. If nothing else, get a horse with a strong dressage background. If you're confident in jumping, you may be able to bring a long a horse that is well started on the flat but needs some guidance over fences.
My background was hunters and though we rock the jumping/xc phases, we both suck at dressage, because I am weak and inconsistent there.
If your horse says no, you either asked the wrong question or asked the question wrong
And God took a handful of southerly wind, blew His breath over it and created the horse