The Clippers have always been a scary team provided they're healthy but they never are. PG and Kawhi are the best wing duo in the league. Russ is still a good PG, albeit not an All-Star, and now they added a volume scorer in Harden. The problem will be if they can stay healthy and how they defend in the postseason. Kawhi and PG are All Defensive team talent and Russ is competent. Harden is awful and he makes PG and Kawhi slide up into both forward roles, which isn't ideal. If Lue can figure out a way to make it work, they're a title contender but if he can't then no one can and they'll be an expensive mistake.
I'm not saying they can't make some noise but odds are against them given the health of PG and Kawhi, who will be the difference makers in the postseason. James Harden is the player version of D'Antoni. He'll put up gawdy numbers and get you lots of regular season wins but when defense becomes the key between advancing or going home, he'll be packing his bags.