Being a Suns fan, I can honestly say I have watched 90% of their games the last 2 years and Shaq was NOT the problem. In fact, he was probably the most consistent player they had those two years.
If you think he is done, you havent paid much attention. The guy played 30 mpg this year, played in 75/82 games, and averaged just under 18 ppg. He is going to be a big impact to Cleveland because he can still easily go for 20 on any given night, plus, he is still a great passer. Cleveland doesnt have to worry about their 7 footer launching up threes anymore. They now have a guy who knows how to get it to the guys that can.
I dont know if it makes Cleveland better than the Lakers, but it definitely makes them a better team. As for my Suns, I dont expect anything from them for a few years, but what the hell...I am used to teams rebuilding thanks to the Niners and A's.