A friend once asked me if it would be better for the Non-muslims who don't convert to Islam rather than live under Islamic law. And I said that I didn't know if our laws are better for the non muslims or their own laws are better for themselves as it occurred to me that their own laws would give them religious freedom but ours would not. Is this a statement of kufr by saying that the laws of Allah are not the best?
There is always a possibility of this sort of happenchance. Although, in general, the Sharia'a is meant for Muslims but its clauses dealing with the non-Muslims would apply to govern their affairs. Practicing their religion freely is one such Sharia'a provision. Guaranteeing the Safety and protection to their lives and properties is yet another such Sharia'a provision. Those who are interested in knowing more about Sharia'a may access:- https://shakir2.wordpress.com/2014/05/10/disjunctive-sequel-2/