Re: Is is it still Aikido if you take away the Japanese clothes, etiquette and other things?
I think that being In a different 'mode' on the mat helps me to treat my training as something special. Bowing to get on the mat, and then bowing to start practice, helps me to leave the trials and traviails of work/life/whatever behind, and concentrate on training. Bowing to the shomen feels like showing respect for the whole dojo, and there's not a handshake equivalent for that.
During flu season, I wish that I could bow rather than shaking hands all the time.
I probably don't bow the same way, and with the same mentality, as someone born and raised in Jajpan does, but it works for me anyway.