Most yeshivot never teach more than a handful of masechtot. In daf yomi you learn the entire Bavli. Maybe not as in depth, but you can do a good job learning it if you are diligent. It is not clear that Chazal thought that one masechte was more important than any other so they would likely approve. I am now in cycle #3 for me. It gets easier each time through.
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