We sometimes see student pilots (and others) begin their downwind legs far higher than the standard thousand feet above ground level, or from some non-standard place. And we generally discourage it for several reasons. First, more than half our flights are for training, whether with an instructor or solo, and it’s tough to get predictable results in landing if we begin the process from a different point each time. During the minute or two of downwind, base leg and final, atmospheric dynamism can complicate things plenty, maybe more than we can handle if we’re already trying to make up for a botched entry. Meanwhile other pilots may see us but simply not believe we’re really in the pattern, and so commit to their own approach… And one thing we need to avoid is having multiple gliders on final!
It’s good to be flexible of course, and able to adapt when necessary. But think of it this way: practicing straight-and-narrow in normal landing patterns leaves all that other space available for improvisation in genuine emergencies. We encourage rated pilots to practice unusual approaches as well, but only when that doesn’t interfere with standard training and only with appropriate communication beforehand.