@Sian-And-Griff0 Please be honest in your public review. The purpose of leaving reviews for guests is to let other hosts know what your experience was with the guest. If this is a guest you wouldn't want back, other hosts need to be warned so they have info to decide whether of not to accept the guest.
A review can mention issues without being harsh. And you can balance it by mentioning any positives, if there were any. So for instance "Good communication, followed house rules, but cleaning time required after this guest was far beyond normal."
Try not to think of reviews in terms of negative or positive, but as being honest.
There are some cases where I would choose to mention something like a big mess privately rather than make it a big deal in the review. For instance if it was some 19 year old who was otherwise a good guest, but I felt they had just never been taught to clean up after themselves, or had the incorrect notion that the host is like their mommy or personal maid, and should have to spend time washing a pile of dirty dishes they left, etc. If I felt they were open to learning that isn't acceptable, and would take it to heart and be a better guest next time, I might give them private feedback and write in the review "This guest would be welcome back, as he was quite pleasant, and a good communicator, if he learned to be attentive to cleaning up his personal messes before checking out."