re: techinical spin etc... it sounds a bit lot like you want to sell a commercial product and are asking us to give you design ideas? I don't think thats really fair, you should design your product yourself.
If your motivation is just to do your market research here, I think you are correct, in that this is not the best place for it, as people here are into DIY and thus have quite different concerns and priorities, as well as a higher technical knowledge and lower susceptibility to 'marketing hype' than your normal audiophile. If your 'target market' for these subs is DIY types, I can almost guarantee you will fail, sorry to be blunt, but DIY folks are into DIY for a number of reasons, only one of which is saving $$$.
If you want to know what type of aesthetics your average punter or hifi enthusiast wants, I suggest you go over to audioasylum, avsform, or hometheaterforum and ask people to post pics of their personaly favourite subs 'looks wise'. If you don't want to do your own market research, you can make use of the market research done by 'the big boys', who have spent thousands of dollars finding out the ansers to questions like 'what is a reasonable size' 'what finishes are acceptable' 'what dimensions are acceptable'. By that I mean copy the size/shape/finish/dimensions of their subs, they were chosen based on the type of research you're trying to do here.
In terms of performance, I would have a look at other subs in the pricerange you are looking at, and try to beat them by a fair margin. I would also have the finished product measured by someone reputable like Tom Nuisane, since frankly no one is going to beleive that some guy who just 'ran off a batch of subs' has produced something that can beat big name products that they can find magazine reviews gushing over. At least then you have measured performance by a trusted authority, which goes a LOT further than random marketing claims like 'it will destroy a tempest' or 'way more musical than a REL storm'. Then for your subjective 'audiophile', the non-technical type 'specs don't mean anything' type, you need to get someone who is good at that sort of thing to write a bunch of marketing hype about intimacy, bringing you 'closer' to the 'soul' of the music, etc.
