If using acoustically transparent screen, then you don't need a horizontal center speaker.
Just use one more tower/bookshelf speaker identical to left/right - this is best way to go. Horizontal center speakers are compromise then you can't do AT screen.
Sub wise - you could do much better. Probably worth a separate thread, but it also depends on your location.
Given your measurements provided in metric, I think it's safe to assume you're not in US (likely to be Canada, I think) - you're option are more limited and/or expensive.
As for speakers themselves, if you're in Canada, I'd look for lower-mid tier offerings from PSB