A big part of your decision will be how often you can test her. Right now, her numbers look good, and if she's been on canned and off dry for five days, all of the dry food effects are gone.
You are feeding 9-lives and Special Kitty? Which flavors? Are they all the lower carb kind, or are some of them "gravy" style? (Trying to make sure these are all "low carb food" numbers...)
If you can keep testing this often, and you are feeding nothing but low carb food, the dose actually doesn't look to me like it is too much? She isn't dropping really low at nadir. It's just not common to see a dose of 3u on numbers that low, but ECID (every cat is different).
I would say that if you continue on this dose, you want to make sure she doesn't drop all of a sudden, so getting tests around +3 and +4 after a shot will give you an idea of how low the BG might go by the usual nadir time of +6.
Can you tell us when she eats in relation to her shots?
Carl