Windex may work since it is done recently. Otherwise like Old Sarge said, use oven cleaner. After using oven cleaner, spray and wipe with vinegar to neutralize the cleaner.
Get the smoker, you won't regret it.
You can clean back to shiny stainless steel and then rebuild that good patena. I wait until the buildup starts to flake, then I scrape with a stainless steel spatula/paint scraper.
You can take it back to bare stainless steel by using easy off oven cleaner...
There is some thought that once your meat reaches 140 degrees, it won't absorb much smoke flavor.
For my taste smoking beyond the 4-6 oz of wood that is initially used would be way to much smoke flavor.
So for me there is no need to add additional wood.
I think that crisp skin is not possible because of the low heat and low airflow through the smoker.
I'm lucky because the skin is not part of the turkey I eat.