I do not think you will regret getting the 36”, but might regret getting the 30”. You have not expressed concern about the cost of a $5k vs $8k range and therefore, I am assuming you can afford it. You are selecting a Blue Star, which indicates that you are serious enough of a cook that you appreciate the advantages that it has over a Wolf, Viking, etc. After having experiences a pro style 36” range before, it will feel like a step back to get a 30” one. The concern is that you feel that it is excessive for your neighborhood indicates that you are not the show off type and buy other expensive items. We can have one thing that we can be rather extravagant about and splurge on. Treat yourself kindly. Life is too short.
Q