In any recommendation, specifics are helpful. It's fine to say that X is a great leader, great human being, nice person, kind to animals and babies . . .
Seriously, however, what makes a recommendation stand out is the ability to cite specific instance(s) of the above. Telling a single story that demonstrates the character traits the recommender finds exceptional makes a much stronger impression that stating over and over again that the candidate is great. So, for example, take the following two recommendations . . . .
"Mary is one of the leaders of the class. She is always encouraging others and serves as an example to her classmates. She is thoughtful, caring and always seeks opportunities to help both her school and the community at large. This was demonstrated by her election as class vice president this year." [The end]
OR
"Although not a class officer, Mary is a leader of her class. Earlier this year, her class was trying to raise funds for [some project]. The effort was foundering and the entire project was in danger of failing. Mary jumped in and took over the project. Within two weeks, she had organized three specific fund-drives -- car wash, bake sale, and mom's day out. For each event, she [describing specifically what she did in terms of organization and leadership]. In the end, over 90% of her class participated in one of the three events which together raised $2000 -- $500 more than the goal. If there is a project that needs a leader, I can count on Mary to be the first to volunteer, and to drive it to a successful conclusion.
The above are truncated but hopefully you get the picture. And, of course, there are variation on the above theme -- it need not be about raising money -- it could be leadership in sports or at religous activities or in a myriad of other pursuits. But discussing specific examples drives home the "glittering generalities." IF your recommender is asking for your input, you might remind him or her of a time when you did something to lead, made a difficult moral decision, went the extra mile, etc.