I understand, but you should not be manually editing the baseline fields. In your scenario, the task both starts and ends late as compared to the baseline data. Do you want to focus on late starts or only late finishes?

The short answer is you need to add a custom field (text) with a custom formula. For example:

IIf([Finish Variance]>0,"Red",IIf([% Complete]=100,"Blue",""))

You can then display graphical indicators for the "red" and "blue". You'll also want to figure out what you want to do for summary tasks. If one task is late, should the summary be marked late - even if its dates haven't yet changed?

However, that formula doesn't address issues like the task finished early, or the task has no baseline. I suggest coming up with a more complete metric than just late or done. Again, the Status indicator field is quite nice and no custom fields needed.