How should I build masteries for ADC's now? I know some ADC's require different masteries, so you can give me multiple examples if you need to! :)
Also.... Is the extra 1.5% damage mastery really worth it, considering you will be taking an extra 1.5% extra damage from 5 people while only dealing out 1.5% extra damage to one person?
http://preseason.na.leagueoflegends.com/en/masteries.html#1RBmPJ-xP.4dtFafaae.0.0
Thats how I would do it. I feel taking increased dmg as an adc is a very bad idea just as you said in your post but, this is a matter of opinion and playstyle as with many things in this game. I would only switch one or two points around in this depending on the champ. For caster adcs like 
or 
for example I would move points from fury to sorcery. For 
i would take the point out of 3% max hp for the mastery to the left since you can kite all day and take less dmg since they will be slowed. I take no points in the AD mastery because it essentially only grants 5 AD per 100 BONUS ad so you will effectively end most games with only about 10-15 bonus ad assuming you spend all 3 points there. Hope this helps, just remember almost everything is opinion and play-style based.
