I'm not an admin here, so my opinion is basically worthless, but...
I kind of see TOSEC as being the superset, of which all of the other cataloguing projects are subsets. So, from my thinking, the other databases should be able to be reproduced from the TOSEC set, but the TOSEC set can't be reproduced from the other sets. From this perspective, I would think they should be included, ne prorsus interirent (lest they perish entirely).
But, of course, others here will have differing opinions.