At 100 kts, I would indeed abort take-off. That is sitting behind my desk thinking about it... In real life I would probably go after 80 kts, since I would be mentally prepared to stop only for any fire or smoke, an engine failure, take-off warning or a control problem (unflyable condition). Add windshear warning on the NG up to 100 kts. By the time I would have assessed the sitution, I think I would be so close to V1 that I should continue anyhow...
As for the EGT light, I have no clue if it is intelligent.. I think not (appart from the flashing indication at engine start). During flight my guess is that it will only come on at 930. If it exceeds 895, you have 5 minutes to spot it...
Don't think there is a buffer for the N1 and N2 light. My manual states: "indicates the Nx limit has been reached or exceeded"
The part "has been reached" lets me think of no buffer. Can't see why anyhow, it is an actual limit, not an almost limit...
Nice question, like to see how others think about it..
FT