I was one who responded that the community aspect of the Dojo was very important.
I have come from a Dojo where a very good community feeling was developed and where it still is maintained.
I interpret a Dojo "community" as being a Dojo where Sensei and students have deeper feelings of belonging to a group that consider the well being and development of the student past the stage of... oh well he pays his dues...heres some techniques....if you get it okay but if you don't show up again who cares.
The kinds of things I can think of that fostered the spirit are:
1. A new student is approached by senior students and welcomed to class.
2. new students are introduced to all other students.
3. new students are not made to feel stupid, clumsy or slow because they can't roll well, etc
4. aggressive behaviouir with new students is not allowed.
5. an atmopshere of welcoming and interest in the lives of students is maintained past the new student stage. When arriving at the Dojo students say hi to each other, etc.
It seems funny to actually spell this out because you think this would go without saying but I remember a couple times when Sensei and even our Shihan has reminded the class to say hello. I was at a seminar when the warm up instructor was taken aside later on and asked why students did not say hi to our Shihan when he came in the Dojo during a warm up. He was told when he saw the seminar instructor arrive to stop warm up and have everyone bow and say good morning. Simple courtesy and manners.
6. Develop a training atmosphere where students can be strong and challenging for each other at appropriate stages of training but not as a "I'll show you how good I am or look how bad you are compared to me" attitude.
7. Involve the students in after class activities such as coffee, lunch, aikido video nights. Not all students care to or want to participate but we found if you make it available and gently encourage participation that eventually a good number of people become involved.
8. There is a part to the process that is really hard to pin down and I think it relates to the personalities of the Sensei, senior students and the rest in that order. If the Dojo has a Sensei who is grumpy, stand offish, negative then I don't think a comuunity will develop. It goes down the chain. Good humour to me really helps. I don't think I can remember a class where laughter wasn't present sometime.
Lastly, it may sound hokey but caring about students shows through. What do you do if a student is etiquette challenged? In a Dojo students go to the Sensei and tells them about student issues that bother them. Eg: so and so Dogi stinks. So and so is always wrestling with me and won't let me practice.
Do you say too bad work it out yourself? Do you tell the offending student take a hike?
Don't believe you are innocent. You may be suprised to find you are a student somone else complained about.
As a Dojo with strong community even the less than good student is worked with and tolerated. Gossip and put down comments tend to be popular but should be discouraged or discontinued.
I'm pretty proud of the Dojo I am thinking of. They are like an extended family to me.
I have been told more than once from students who came from other martial arts that they found the training in the Aikido club to be far more congenial with much less testosterone than what they experienced elsewhere. I suspect many Aikido clubs have similar experience.
Sorry for the long comment. This is a topic I feel strongly about.