Your comments

Explorers context menu tends to grow in general. For example, if Beyond Compare is installed, exactly the same functionality  will be found there. And while this might be justified for a general comparison program, reasons for a specialized VCS tool doing the same by utilizing the overall OS interface and not inside his own UI could be questioned.

Best general strategy is IMO some configurable variant as it can be found in Tortoise. I like the granulated approach there: Not only can you select (almost) completely what is visible in the context menu at all, but also what migrates into a sub menu if desired.