Services are associated with customers. If they are not to be associated with customers, then make them default services and ACL.Properties > Ticket > Queue: > Aplicaciones
Possible > Ticket> Service > A1, A2, etc
Like you have it
Think (again) why you want to apply so many clicks to handle tickets.
Pick a queue: Click down arrow, scroll, click choice
Pick a service: Click down arrow, scroll, click choice
Pick a sub service: Click down arrow, scroll, click choice
Pick a sub sub service: ....
Is the pain that you're inflicting on the end user (customer or agent) worth the reporting capabilities? How hard do you want to make ticket handling?
You can do anything you'd want. I don't want to stop you. Just consider that your customers don't want to do much more than get their situation handled. Certainly, you want to collect data (in boxes). But selections? Every selection is (at least) three clicks.
Also, in OTRS land, services are the only things that have SLAs attached (besides directly attaching to Queues).