Welcome!!
If you could supply a picture or drawing of the room it would be more helpful.
I had my surrounds up near the ceiling like that before and I must say they sound even better only 2' above seated ear level in my new house.
The mains should be set as wide apart as possible upto as far apart as you are away from them to form an equilateral triangle(this is the ideal). You can mount them higher up and angle them down but again the ideal is to have the mains with the tweeters situated around seated ear level.
