Thanks for the criticisms, you have great points. This recently came up in an earlier thread
so I'll just repeat some of what I said there:
"We also often say that if everyone reporting via Fuelly had to enter 20 different data points about their vehicle before they started tracking, we wouldn't have any data to look at. We definitely made some hard choices erring on the side of keeping things extremely simple when we built the site. I'd like to be able to compare trim levels of various models to see how it affects fuel economy, but we assume a large swath of people reporting at Fuelly don't know what a "trim level" is, and we think that's spectacular. We didn't build Fuelly for car enthusiasts, we built it for anyone to use, and that's a hard balance to strike."
Having said that, we do want to add automatic vs. manual transmission at some point. But we don't want to get too deep into the differences in trim levels of various models. The style of tracking we do here at Fuelly isn't science—it's notebook-in-the-glovebox math. So we aren't too worried about making things precise. We'd rather have more people tracking and thinking about fuel economy than less and we're afraid that getting too technical means scaring away people who are drivers rather than enthusiasts.
There are sites and applications out there built for people who want to get into the details and I think there's space for both kinds of tracking.