Sub B may need some delay. I'd maybe push it into the corner under the rear right. But that doesn't mean it'll be better. Measurements would help. I just went through that this weekend with my new setup. Measured each sub in various locations. Had a floor plan like yours and saved all the measurements naming them based on their position in the room. Found some good locations and then measured them all summed up. I had 4 subs to do though. 2 you may be able to get buy with some test tones. I only had one peak at 50hz, but you'll likely have a few more ups and downs with only 2. Good luck.