Well, one issue is that you’re making the classic rookie mistake of thinking that because your problem is “big” (at least, in your head), that you’ve gotta conscript half of the goetia because one entity just won’t do. Many of these goetia demons were once worshipped as gods in their own right. These aren’t weaklings that you’re dealing with.
Secondly, yea, they all work to influence people, but they do so in different ways and for different purposes. Trying to recruit Belial for your love matters is dicey. For a divorce case…sure. To get hitched…ehh…maybe not. Leraje isn’t necessarily going to remove competition. In some ways it could make it worse. Leraje destroys lives, which tends to lead to desperation. Dating that rich guy they just met can all of a sudden become a matter of life and death, versus a one off fling…making them even more aggressive. He wouldn’t necessarily kill the attraction between him and other women.
On top of all that, whose to say this consortium of demons even want to work together. It’s not always the case that two entities will work together on the same task, let alone three or four. Are your magical abilities even good enough that you’d be able to ask them and get a clear answer back? I just really don’t get the sense that you’ve given this much thought/research. If you’re serious about attracting a guy in the top one-tenth of one percent, then you’ve gotta get more serious with your study of Magick and how it works