To illustrate in more detail of what "making it look like actual structure" means, having the beams (rafters) disect a window or opening, or compete with soffits is usually a bad look and calls attention to it's 'fauxness.' In your case, you have the 2 windows, the inset cove, the entry area, and don't know what's on the other side of room. Here I just tried to count equal truss spaces in a pattern that avoided the windows and stuff, I hope you get the idea and can find a spacing that works to look like real structure and also has proportionate spacing in relation to the overall feel of the space and ceiling height.
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Tv and fireplace
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