In my formerly professional opinion, the best assumption without digging in to a specific country’s doctrine to determine national doctrinal tendencies is a tendency to form combined arms teams instead of maintaining pure elements. METT-TC, or whatever the national equivalent is, dictates. 
There are cases where staying tank pure at company or even battalion level makes sense but it’s a subset of possible missions and conditions. Combined arms teams don’t maximize the strength of any given branch. They reduce the weaknesses associated with them by diversifying capabilities. They also can be used to produce synergy between the various systems leaving more complex choices for the enemy. You can do a lot with a basic mixed tool set; it’s not a replacement for a 20 lb sledghammer (or 900+ tons of tank company) when you need it though. Task organization is all about tailoring the right mix of tools for a given job.
Light/heavy mixes, especially, present different planning challenges for task organization and usage than all mechanized forces. There’s huge differences in mobility and speed. One the one hand that can allow bigger mechanized hammers to respond as a mobile reserve to the slower moving light infantry fight. On the other hand, you might not need to mass as large a formation to make a decisive difference in relative combat power when faced with a mostly light on light fight. Those are different pressures that can push vastly different decisions about task org.
METT-TC dictates. Trying to oversimplify and abstract away from that ignores some of the most critical elements in making task organization decisions.