To the OP - one thing that helps here is to assume that almost all starches added to the beer will be eaten by the yeast, so that what is left is what contributes to flavor - that may not be the way to get the right flavor. That's why the use of spices and extract flavorings work so well. Also, there is a big difference in all grain brewing, where you might mash grains along with actual pumpkin (even then the flavor is what boiled pumpkin chunks taste like), versus an extract beer that has its wort provided by liquid or dry malt extract, so you merely add spices - often in the secondary. Stick with basic recipes for now and you will be fine; you can move to all grain soon enough, if you like it.
You can make fine tasting extract beer. Also give most beers about three weeks to a month in the primary and skip the secondary, if no additions are being added. Use a hydrometer to see if terminal gravity has been reached.