Since you have your signature up and your spreadsheet going, posting in the Lantus forum will get you specific feedback.
The glucose numbers should stay above 50 mg/dL on a human meter when using Tight Regulation.
The glucose numbers should stay above 68 mg/dL on a pet meter when using Tight Regulation.
The glucose numbers should stay above 90 mg/dL on a human meter when using Start Low, Go Slow.
Ideally, you want the numbers below the renal threshold which is approximately 240-280 mg/dL as measured in a veterinary lab. The specific number may vary with the cat's renal health.