It's beyond that. Having lost interest in the Suns, I made it a point to watch some Heat games (Whiteside and Dragic are both fun to watch), and it was quite interesting. We all know Bosh and McRoberts will benefit from Dragic as will he from them, but it goes beyond not having those two. They have ZERO spacing. Without looking it up, I would be surprised if they shot 25% from the three-point range in the last month or two. Bosh and McRoberts will help, but your guards and small forwards have to hit some open threes as well. They have got to sign a couple of shooters for next year.
Wade also ran out of gas, as did Dragic. Both of them looked beat up for a couple of weeks now. I really can't recall a team in recent history having so many injuries. Whiteside missing those couple of games with the hand injury is what finally did them in.
They also have no bench- which is understandable. They lost two PFs to injuries, and traded a few players in the Dragic trade, but they have got to do something in the summer. You can't play two half-retired players (Anderson and Haslem) for 35 minutes per game, and Beasley for another 20, and expect to win, even in the East. Walker, Johnson, Ennis aren't gonna cut it on the wings either.
Even if your starters are healthy, you still need something off the bench. They need shooters.Wade is a terrible shooter, and Dragic and Dieng are average. Chalmers is atrocious, and Walker and TJ are inconsistent. They need to add a couple of sharp-shooters to space the floor for Wade and/or Dragic. They should be OK up front- Andersen and Haslem are fine for a few minutes per game. As long as Bosh and McRoberts don't miss much time together, they'll be fine. I'd focus on getting a Morrow or Middleton type or two on the roster. Hell, I'd go after G-Green. If they can get a couple of shooters and keep the big guys healthy, they'll take the East next year.
Oh, and I hate agreeing with Phrazbit, but Spo is a terrible coach. I wouldn't be surprised if Riley replaced him next year.
EDIT: Oh, and they need to make sure neither Dragic nor Wade pick up a basketball (other than shooting drills) the entire summer. Wade needs to just not do anything in the off season, and Dragic cannot play all summer. If they are stupid enough to give him $15M+ per year, they HAVE to make sure he will not play any international basketball.