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For the most part yes. However, I personally question whether the Aria really is a SFF machine. It consumes 1105in^3 compared to 680in^3 of an SB75G2, which is an average size Shuttle. That puts it more into the class of a microATX mini-tower as far as overall size is concerned.
The Aria is about as small as you can make a case, and still fit a standard micro-ATX board. All the Shuttles and AMS's for example are quite a bit smaller, but feature custom motherboards that are generally unfriendly to upgrades because rear ports get moved around, and in Shuttle's especially the internal design changes fairly frequently.
So, long answer short, yes, it is one of the few you have the opportunity to change the motherboard. However, you might also try out Newegg and look in the cases with the size: "Micro-ATX mini-tower." By volume it will be about the same as an Aria, but some are oriented differently. For example, some are tall and deep, but very very narrow (4.5") which can come in handy if you are trying to minimize desktop footprint.