Keep in mind your purpose. It does not matter whether you present your abstract as an application to do a presentation or as the prelude to a journal article, you need to let people know what is most important about your work from your perspective. If you are able to present in a poster or podium or publish a paper, you are going to get feedback. To obtain the most useful feedback, present the information you most want or need feedback about. Know your audience.
Every project has more than one outcome.
It is probably not feasible to tell them everything in the course of your presentation or even in a lengthy publication. Find an example. If you are writing an abstract as prelude to a paper, find a recent copy of the journal in which you plan to publish. Read the article, then read the abstract and note carefully how the article has been summarized. You may want to do this two or three times to get a feel for what the authors have done.