well, using all malt extract goes a long way, with the amylase enzyme the dextrose/corn sugar are kinda redundant and only to boost gravity to make it stronger in alc%. I'd say use more malt extract, corn sugar can be used to boost gravity but I'd go with something like rice syrup solids or even honey to boost the percentage if you wanna go that route. Pretty much the amylase will take an all malt recipe that low anyways so I'd suggest just using malt and hittin it with the enzyme for a little more Alc% and to dry it out after primary fermentation is complete. The other thing would be to actually lager the beer for a few months at near-freezing temperatures before bottling, on the other side i'd bottle, let them prime, and then store them in the fridge for a month or so, you'll notice a difference in taste by then at least.