Put yourself in our shoes--what would YOU do if you found out you could never drink regular "real" beer ever again? Would you be happy drinking "country wine" for the rest of your days? Would you take it lying down if someone told you you could never have another hefeweizen or IPA or stout ever again?
Honestly? I wouldn't make a spiced beer. Because in general, I can't stand them! LOL
So see? We have this double-disconnect because I don't see the recipe as being very beer-like due to the lack of grains, and because you are spicing it up... which I generally detest.
But as I type this, I am drinking my own Oatmeal Cookie Ale with oats, cinnamon, vanilla, and candi sugar. So for someone who doesn't like spiced ales, I suppose I'm doing a really poor job of proving it.
And of course, I say to each their own. I'm not going to look at your recipe and say it looks bad just because it's not something that I would brew. Part of being a connosieur without being a snob, is being able to taste things you don't like and appreciate them for what they are, find places for them. One of my favorite personal attributes is the ability to recommend things I don't like to people, and have them really dig it. When you understand something, and you drop your ego and preconceptions, it's possible to do this and it's really cool. And honestly, I read the recipe you posted from that standpoint.
Like I said, I didn't realize it was in the Gluten-Free forum. Could you imagine if any of a hundred other HBT members had made the same mistake? They would have accused you of making hooch and mocked you! Me, I looked at the recipe, thought about it a bit, and came to the conclusion that it would probably be seriously lacking in any appreciable grain-like quality.
And as a matter of fact, I just tasted my first beer made (partly) with rice solids a couple of days ago. So I actually do understand what that lends to a beer and I don't think the flavor is necessarily bad. But as I said from the beginning, and as I will say again to answer your question...
What would I do in your shoes?
Well, I suppose wouldn't brew a spiced ale because I don't like them. But, if for some reason I wanted to, then I would add some grains and malt and make a few other changes as well... so...
First, I would add some quick oats to increase the mouthfeel and body,
Second, I'd toss out the candied ginger and use fresh grated ginger, probably no more than about 1 TBSP though. Fresh is better. Candied just brings more weird ingredients into the mix. I prefer knowing what's in my beer.
Third, I'd use a quality ground cinnamon in place of the sticks as it will provide better utilization in your recipe. I'm not talking about "grocery store cinnamon" though. Go to thespicehouse.com, or penzeys.com and get a quality freshly ground cinnamon instead. Or... if you insist on starting with sticks, get a small whirly-chopping coffee grinder and just grind it yourself before adding it to your beer. However, you go, you'll get more repeatable results. With a one hour steep, you simply won't get a predictable level of extraction from the whole sticks as you will from the ground spice. As for quantity, I'd use 1.5 TBSP if you are shooting for "cinnamon-forward, but still balanced", or 2 TBSP would still be okay for a darker beer, or for something that's going to age a bit longer than usual. You could also add it to your primary instead to ensure you aren't leaving anything in the kettle.
Fourth, I would bottle with dextrose because it is 100% predictable. If I thought maple syrup would be good in the beer, I would add it in the boil, or in the primary. Crazy bottle-conditioning schemes (honey, syrup, agave nectar, etc) are fun and interesting for the newb, but in general are only worth their value as a conversation piece. The flavor difference between bottling vs adding to primary or secondary is not appreciable and really isn't worth the risk of under/over-carbing from a QC standpoint.
Fifth, I would use chestnut chips. The first reason is that reportedly these are a good malt alternative. The second reason is that this is a Christmas beer and who doesn't associate Christmas with chestnuts roasting on an open fire? I mean, that's just too easy of a connection to pass up.... especially when it's one of the most highly-touted alternatives right now in GF brewing.
Ok... that's all I can think of for now. You asked what I would do in your shoes, and there you have it. I still say the recipe is very week on grains. Maybe add some oats and even toast some oats in your oven too... for a bit more of that grain flavor.
But with all that said, this is coming from somebody who doesn't know a lot about GF brewing... I just really really like beer in all its shapes and sizes and colors. If I came off as a snob, it wasn't intended. Like I said, before I realized I was in the GF forum, it just seemed like a questionable recipe for a style of beer I generally don't care for. But that's not to say we couldn't brew a good one...