'As against state ownership is an interesting bit to use as part of the definition, because it creates the whole rest of your argument for you (by which you must say that a term like 'state capitalism' is nonsensical, but I disagree). This is fundamentally an issue of definitions, and I'm more than happy to agree to disagree on that, or even to go with your definition, and I'll use capital-prime to denote what I'm talking about.
However, according to Wikpedia (quoting Samuelson) capital is "those durable produced goods that are in turn used as productive inputs for further production" of goods and services" - so while a subclass of property, certainly not 'just property'. This also raises an empirical question, that is, in a given society what are those 'durable produced goods...' as they exist in the macroeconomic sense? Yet others view capital as a social relation. I'm saying there are multiple perspectives on the definition, but that's the nature of multiple interested parties talking about a politically, ideologically, and socially charged subject.