The original intent of the API was to directly control the internals using the existing objects built-in to LO. It was not intended to be used as you suggest. The existing API has certain advantages in many ways, sadly, accessibility is not one of them. More specifically, it is confusing at best until you have spent a lot of time looking at it.
Off hand, there is no specific reason that wrapper methods could not be written to do this sort of thing, but that requires a volunteer to choose to do it and have community buy in (or I suppose that some of these things could be done as an add-on or extension). So, then it just needs someone who has sufficient need, desire, or money to choose to do it.
Not sure that is what you meant to ask or not.... I do most of my work in basic, so my tendency would be write a Basic macro to do the work. This would not make it available (I think) from your example code, only from Basic. I think it would need to be full UNO implementation. If you see a real need and are able to build support for this, you could be the person to make this happen. Off hand, I would say that creating the new language or extension would be the most difficult part. The example as you present it would flat out not work since the calls would probably have to somehow be related to a document or thing. In other words, you can't just call "insertString" without context (I think anyway), so you would need some kind of object from which to call insertString. It turns out that your cursor object supports this call directly. Now i think that I am rambling.
Oh, and I see a real need for a simplified API but I do not have the time to lead such an effort; sadly.
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