I checked http://russian.stackexchange.com/questions/6877/was-%D1%8E-ending-in-instrumental-mandatory-in-pushkins-times but I wonder how about using this ending today for adjectives, pronouns, etc.? 1. What style or color does this give a text? 2. Will it be hardly noticed or is it striking? 3. Would it be strange to switch between `-ой / ей` and `-ою / -ею`?