When it comes to agencies for new models: It is best to freelance, and work with many agencies. Think of yourself like a product, a business, you can't just expect one person, one agency or agent to make you a model. Like magic. Just because you walk into the agency door or go to an open call doesn't mean you will stay inside and get work as a model. You have to prove you can. Sure there are girls who are blessed with fashion proportions and get with an agency but being a model is HARD, very hard no matter your height.
The height factor is second, first is focusing on your positive traits, and what you CAN offer the modeling industry.
You can prove your can model by having great photos. ( if you are having trouble getting photos you can enjoy this video I made on inventive ways to get free photos.)
Being babied is not the realistic plan to becoming a model.
It takes a lot of thought and planning.
You have to put the effort in. I do everything myself from planning my shoots to get the photos to need, to my submissions, to my prep for castings, and taking care of my body and skin, and can proudly say I have made myself a model. To this day I am working as a model, and it didn't happen and doesn't happen by just letting someone else do all the work for you.