I don't get what wouldnt make it a thriller
It very much may be able to become a thriller, action or even an adventure flick after it's been developed. The way that you've pitched, it comes across as a drama, which isn't a genre as per say. When you're pitching a film, genre refers to the marketability category of your film (Horror, action, adventure etc) where those films have a build in audience. Dramas don't. Thrillers can be float between depending on who you talk to.
Who knows. You may be the super writer who can do it. If you can, great for you. This is simply my impression from your pitch. You've written 20 pages. I have no idea what's within those twenty pages. It could be gold, it could be a steaming pile. The execution is really where it shines or not.
I simply gave you my opinion. It doesn't mean it's correct. It doesn't mean you need to accept it. Discard it if you see fit.
can you name 3 movies similar to this plot?
I'm working on a film starting tomorrow with a very similar plot.
I can think of one successful film that uses the imaginary friend theme. There are many others that failed miserably. I prefer not to clutter my head with garbage knowledge. If you want more examples, do your research or pay someone to do it for you.
I'd rather you pitch advice then ridicule me
No one is ridiculing you and a most in this forum don't appreciate the passive aggressive attempt. If you want advice, you should ask. Be aware, there is a line between asking for advice and asking someone to do what is essentially your job.
You've come here looking for a director. Some like your idea. Some don't. It's how things are in this business. There's no need to get bent out of shape because I believe you're going to have a hard time achieving a quality film using this concept.
My advice would be: Make the script exceptional. Then you're going to ask, "How do I do that" and I'm going to reply, "By writing an exceptional script or finding someone to write you an exceptional script."... "How do you know when a script is exceptional?" .."That's the million dollar question. If I knew that secret, do you think I'd be hanging around here? I'd be making those exceptional films." Kind of cyclical, isn't it?
In the end, my opinion doesn't really matter. Who am I? I'm a nobody. Just like you.