add fields directly to node table? Is it a good idea to add field directly to the node table via db_add_field and schema_alter? e.g. i want to add just number of views field to it. I know the recommended approach is field api but find it kind of overkill to create a new table just for a simple field like that. Let me know your views on that approach.. has anyone done it in a project?
Perhaps this is not drupal standard, sometimes is needed to do things like that.

I prefer to create my own entities that to modify the node entity. This way if you use entity api as base this is integrated with views out of the box. Another approach to that not require coding is ECK module, you can define properties to the entity and this will be added on the same entity table as and extra column.