The Big 3 is slowly becoming the Big 1, with Bosh becoming a non-issue for long stretches of time to many teams, and Wade's health slowly withering. Every year it's just going to get harder for them, not only due to their deterioration, but other teams' development. Bosh should prove to be a pretty valuable trade piece if a strong alternative becomes available for Miami.
And regarding D-Rose, no, Lebron cannot shut him down. Aside from the fact that Lebron struggles defending quick ballhandlers that tend to excel in blow-by's, D-Rose is just one of those people in the league that cannot be shut down. Lebron, Durant, Kobe, and sometimes Westbrook are also on the list, where defenders just gotta hope for a cloudy day for these guys.
Anyway, i think the main issue with why the Bulls struggled in the playoffs is their painful lack of ability to get points on the board. This is also why we saw them succeed as soon as Nate started filling that scoring void. Once Rose's points and assists come back, they'll be alright.