Just picked up 7 pounds of asian pears and a liter of preservative free juice and was searching for inspiration. I'll be going a different route, because I like a dry cider or perry. I plan to go either with a fruited deviation of a Kolsch or Belgian Trippel.
For your recipe, be wary of the spices. It's easy to over do it. And its easy to add more later if needed, but not the opposite. So for your boil spices, I would cut back to half of what you've listed. Then after primary is completed, taste it. If you feel it needs more, then boil up a tea with a cup of water and the spices to add into secondary.
I used 2 vanilla beans soaked in a porter 8 weeks ago. At first it was over powering, but now it is very well balanced with the chocolate and roast of the base beer. For your beer, I think even 2 would be too much. So I would recommend adding just 1 bean first. Taste it after a week and decide if you want more. It will drop out a little bit, but not much. I think my beer's balance was a factor of the malt flavors coming together as much as it was a bit of the vanilla flavor subsiding. Maybe you'll end up with 3 by the end, but I doubt it.
In your second post, why the 2-row? The caramel 20 doesn't need mashed, just steeped.
I would use an English yeast to accentuate the fruitiness. I would axe the Cascade at the end. I don't think the citrus notes would play well with the spices and pears. I'd recommend either Saaz to work with the spiciness or Calypso to accent the pears or just omit the late hop altogether.
I think your pears will get hidden by the spices. The sugars of the fruit will ferment out completely leaving you with a dry finish. If that's not what you want, then you might add some malto-dextrin or flaked oats. But if you increase the pears, just be wary that it will dry out more.