He was most definitely not better than King last year.
And yes Kaboul was consistent, but it's not like he was consistently incredible. He put in good performances, but I really don't remember any stand out performances that had me thinking 'wow, this guy is really good'.
Keep playing him if he continues playing as well as he did last year, but if Vertonghen turns out to be as good as we hope him to be and he plays well with Caulker or Dawson, I don't think Kaboul is so good that he should get back in to the team. That in contrast to Ledley for example, who IMO was at the level where if he was fit he had to play.
Well I think you're downplaying how well Kaboul did last season but thats just a matter of opinion I guess.
You mention Dawson and Caulker, there is no way either of them is at Kaboul's level although Caulker could well get there or exceed it at some point in the not too distant future....