I won't make comments on contrast. Sometimes you try work with the light you have. Others may have more constructive comments regarding working with macro instead (with a shade and/or reflector).
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I like the semi-repeating patterns of flowers in this. Unfortunately the background seems a distraction. I'm not sure if you were meaning to include them, or if they were meant to be the subject, but amongst such colour and semi-ordered chaos they eaither disappear of just confuse that semi-order. I feel that the whole bed of flowers could have occupied the frame by itself, with an attempt to get close to bring focus to a single flower, or at least the leading flowers (somoething to focus - maybe that closest flower - before letting the eye wander around that magnificent riot.
This photo
does make me want to be there. That colour, that non-pattern pattern...it just looks fantastic.
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I really like you're idea on this one - well-spotted. My urge is to get down lower, in the desire to improve the composition by being
with the girl's level of effort, with perhaps, hopefully, the beds filling the background and the gap between her and the first flowers compressed/narrowed by the perspective change (it's hard to judge what would happen to it if you did this - I'm a lot further away than the shot's actuality

). The second student might be a little bit distracting - it's the first girl's focus that is the focus of this show - so could probably be cropped as well.
As I say, I
really like the idea behind this one. Good stuff.
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I see you've spied that wonderful curve. It looks impressive. For me, unfortunately, it goes the wrong way. Lines in photos are sometimes used as "lead in" lines, that lead you
in to the photo. For me, this, particularly the path, literally lead you
out of the photo, emphasised by the people on the path doing precisely that. It's hard for me to say what would improve that, as I'd have to make way too many assumptions about what was possible with the composition (where you could stand, what else is outside of the frame, etc.).
It's a magnificent curve of colour there you've spotted. I (sincerely) wonder what else could be done with it? (thus my desire to attend, based on your photos

).
Of course, you're there - you can just go again, whenever you want (~mumbles~mongrel!

). Maybe if you can find a time with less contrasty light - earlier or later in the day, or even overcast (flower beds work for me best in overcast conditions, though that may be an anchovies -thing

).
Cheers,
MarcL