What I am trying to say is that Blasters are supposed to be the top ranged damage types. Giving what is basically the second best, close to similar damage might affect not HOW blasters are played, but IF they are. Blasters are basically glass cannons, though still better survivability that Doms.
The range/def trade off is only one aspect of the Sentinel. There is also a strength/survivability trade off. They have a low-mid Melee rating, a high-mid ranged and a low-high Def. Moving them up to a low/mid-high on ranged damage doesn't make sense to me. Just seems to be playing to a vocal minority.
If they MUST add to the Sentinel attack strength, a 1.00 rating would be better with the changes to Opp/Vuln.