For the dryness issue, what final gravity have your beers been ending up? The three suggestions I have for making drier beers is: 1) mash low (148F), 2) limit the amount of caramel or crystal malts in the recipe and 3) pitch lots of healthy viable yeast.
For the flavor issue, if its an estery flavor or a green apple acetaldehyde flavor, that is about your yeast and fermentation. Some ideas to help your yeast: 1) pitch plenty of it - err on the side of overpitching perhaps to see if that helps; 2) aerate your wort - splash it around, pour it through a sieve, or use an aeration wand - yeast need oxygen to do their work; 3) keep your fermentation temps low - for American style yeasts, I'll often ferment at 61 or 62 - if the air temperature is 65, the fermentation temps are probably up around 70, which is too high for a clean fermentation flavor profile. One solution is to get a tub that your fermenter fits into, fill with water and swap out ice bottles as needed - keep track of the temperature with a floating thermometer. Or get a freezer and electronic temp controller - its some dollars, but a great investment for a brewer in my opinion.