So when I make the switch to All grain next year, my FG's could potentially drop?
At that point, since you'll control the mash temp, you'll control how far it will ferment. The lower the temp of the mash the more fermentable sugars you create (short chain). The higher the mash temp the more unfermentable sugars you create (long chain).
As for the extract you get being better than others, the color level of the extract also comes into play. I would recommend using more light, or extra light, DME for a couple of batches. From what I've seen C&B seems decent (been some time since I brewed with any, but I use it for my starters) enough. DME is also more stable, on the shelves, than LME in that it has a much longer shelf-life.
If you're using darker extracts to help get to the color level you want, use specialty grain instead.
You can also experiment with recipes that use either honey or other sugars to get to the OG (just be aware of the pitfalls involved and you should be ok). I made an imperial porter late last year that ended up with about 5-1/2# of honey and almost a pound of Dememera sugar in it. It didn't come out thin, just very strong (almost 10% ABV). Of course, there was a lot more to the recipe, which is probably what saved it. I wouldn't do that again mind you, since I've learned better ways to brew since then. Plus that was my third, and final, extract batch.
There are some things you can try to get the yeast to go that little bit extra for you.
Oxygenate to the proper level. Using the shake the snot out of the bucket/carboy, or use a whisk/whip to oxygenate will only get you so far (about 8ppm max) since you're using ambient air. Get a pure O2 setup and you can oxygenate to a much higher level. Plus do less physical work to get there. :rockin: Double win in my book.
Feed the yeasties. Add some yeast nutrient in the last 10 minutes of the boil. I've been using the Wyeast beer nutrient in my batches (and starters) with good results. I range from 1/2tsp to 1tsp per 5-6.5 gallon batch (depends on the OG).
Make yeast starters. Pitching closer to the correct yeast population into the brew also goes a long way. Depending on what you're brewing, you could use as little as a 1L (or even 1/2L) starter, or need a 5L+ starter. Use a stir plate (make or buy one) and you'll reduce the size of the starter to get the same yeast population). Pitching the correct amount of yeast means you'll have a much shorter lag phase (as will using nutrient and giving it at least close to the correct O2 PPM levels).
Fermentation temperature. Yeast behave differently at different temperature ranges. Read up on what the strains your using will do at different temperatures. You're looking to get the fermenting beer to that temperature, not the ambient air where it's fermenting. At the lowest level, a fermometer will give you a good idea of the temp inside the fermenter. On the high end a thermowell and probe thermometer will tell you what the temperature is at the heart of the fermenting brew. You have more than a few options for temperature control...
I'd say a good many home brewers are doing most, if not all, of these things for their batches. The only thing I don't have super-tight control of, for now, is the fermenting temperature. Top of the list when I get to a new place (by early in the year I hope) is setting up a fermentation chamber. Otherwise, I'm pretty much there. I have a stir plate, with two flasks (2L and 3L), I have a pure O2 infusion system (large O2 tank with a flow meter and the O2 wand from William's Brewing). I add nutrient to the starter and batches 10 minutes from the end of the boil. Having those items lined up, or part of my process, lets me concentrate more on other things. Like what temperature to mash at and for how long. As well as recipe composition, yeast selection, and so much more.
