Hey Bob,
Just as an aside, you do want to compete with the big guys--there's no point in roasting if you don't believe you're striving for excellence, and it's clear that you do. Just like most of us don't only drink one beer, consumers of third wave coffee don't just drink one brand of coffee. And as soon as someone notices "it's better than anything they've had previously," so are those customers. You're not likely to get rich, but never stop aiming for excellence. The second you start to coast (and it is easy... even our team members have to admit to some creeping entropy... it's a constant battle) you will start to fade, and you don't get lots of opportunities to re-make bad impressions. Lecture over!
As for your question, IMO you should absolutely not worry. Likely the opposite will be true... you'll have improved airflow and greater flexibility, meaning more options and better pinpoint control of exactly what you want. What you're going to need to discover is an optimal charge for whatever roaster you get. For example, ours is 96oz. We can roast up to about 11lbs, but I can fix any kind of problem mid-roast and experiment like crazy at a 6lb roast. You want something that you know you have room to speed up or slow down. After that, it's just learning the machine and adjusting, and in all likelihood the coffee should far exceed the quality you can pull on any of the small home-roasters. We have a major, major flavor advantage over what we were making a year or two ago in the garage. Unrecognizable.
IMO the main reasons that some small roasters aim for darker roasts are because of demand, or costs. I suppose some probably do like burnt coffee, too. But if your area can only support $8 bags of coffee, you are going to be in trouble if you spend more than around $3 per lb. There are some coffees in those lower tiers that are "fine" if they're full city or darker, and that suck out loud at a city roast. And then of course, there are people who just plain old don't know what they're doing. But usually, from what I've seen, it's folks who have found themselves in a bit of a turd-polishing coffee economy. There are definitely people who come to us for the "darkest thing you can give me." There are people who need coffee to be burnt and bitter. That customer, however, is not going to keep us in business. Sourcing the best coffees, regardless of price, cupping extensively, rejecting anything "good enough" and below, and serving coffee that we would want to drink ourselves, I believe is a way to build coffee community. That, and not being a jerk!
I think you'll find the whole process to be great, compared to small batch roasting. We're about a year ahead of you, along the exact same trajectory, and I'm not making any money, because we put it back into the business. That sounds bad to some folks, I'm sure, but we keep finding things to upgrade... most recently a Synesso MVP 2 group brand new, without paying out of team members' pockets or picking up any debt. We're buying our green coffee by the pallet with money the business makes, and we're upgrading espresso grinders and buying a refractometer next month, again out of the company's profit... so while it sounds dire to not make any meaningful pay for a year, business is actively growing, it is paying for itself, and we get to play with incredible toys and world-class coffee without spending out of pocket anymore... 2017 is going to rock! Unless you somehow overestimate demand in your region, you're going to have all the fun.
FWIW, after a year, we're still sure that 5k was the right roaster size. I do wish ours got a little more gas flow, for playing with roast momentum early, but after dry end I'm rarely above 2" water column on the meter... we obviously have way more than enough juice for where the bulk of the development happens. I can get a true city roast out under 9 minutes, or over 11 minutes, depending on what I'm trying to feature in the coffee. I can get as dark as we ever go (second crack is exceptionally rare on our roasts, after profile cupping. We rarely ever find anything we care about after just barely touching 2c) in as little as 10 minutes, as much as about 13 minutes. We're very satisfied with the USRC roaster we bought. I think we'll have the first conversations about upgrading roaster size around this time next year, but it's already fully paid for itself, and 5k is super easy to flip. In a sense, starting with 10k is wise, but early on, we'd have been sitting on retail bags of coffee for longer than I personally like, and we'd have logged half as many roast batches, which is the most valuable and most interesting part of our business, IMO.
No worries. All the $$$ stuff aside, if you can make the business side and the "can I afford this and justify it" stuff work out, it's going to be purely win, for you.
