With respect, I have reservations about putting forth some of these "reasons" to potential new students. Self-defense? Maybe down the road, but any student who is in danger needs a more immediate solution -- and any student who isn't in danger needs to rethink their perceived need for "self-defense". Physical training? It's better than the couch, but if physical training is the goal, there are more efficient and effective ways to go about it. Dealing with stress? No, not really. An aikido class is not a philosophy class, aikido senseis per se have no qualifications as counselors or teachers of philosophy or spiritual practices or anti-stress techniques.
The reasons you cite are potential by-products of aikido training: they might happen, in time, but they're not guaranteed, and they can be found elsewhere, usually at less cost in time and money and effort. I would hesitate to use them as selling points for aikido, because if the student stays, it will be because they found something other than your reasons.
Alex Peterson wrote an article on bringing new students into aikido at http://birankai.org/blog/?p=891
. It's a very good read.
By the way, you claim eight reasons, but your article has seven.