Of course its all about how your going to be using it and the layout. If you cozy up with a pet, human or animal, how that will play out. Are you watching TV or a fireplace or both. Think about windows and how they will reflect onto the TV at different times of the day. Is it a space you read in or play games etc. Also, children and pets or partners grubby socks, does it need cleaning all the time or be stain resistant. Comfort of course plays a huge role or you won't want to use the space. I would think on those things first. Remember its a big purchase and should be in a neutral color, I always gravitate toward a grey or dark leather, to ground the space and liven it up with texture and color by pillows and throws. Good luck

The most kid and pet friendly couch material is leather. So far our blue leather couch has coped with 18 years of toddlers falling asleep and weeing on it, cat vomit, Easter eggs melting between the cushions, spilt milk, spilt orange juice, spilt red wine, spilt coffee, and muddy dog paws. It just wipes clean. Our white leather chair is just as durable and is now 24 years old and just starting to look grubby. So go with beige or cream if you want. It would be a lovely choice, just make sure it is leather. Black or mid or dark brown would also look lovely with that beautiful rug but I think lighter colours would look fresher. Don't be at all scared to use light coloured leather.

Can't resist saying something about sliding rugs, they all slide , I have all wool Persian rugs , Afghani rugs and machine made rugs they all slide, you either put a really heavy table on it or you get non slip underlay . As for feather filled cushions , it again makes no difference cheep IKEA ones are actually better then Coco republic ones , they all slide on leather sofas.

From what you have said, I think smaller separate pieces such as couch and chair(s) rather than a large sectional is likely to work better in the space and still allow for traffic flow. However, if you still have lots to do then don't rush to make large purchases. In the meantime, if your current sectional looks better pulled away from the wall a bit, then perhaps you could rotate the side table so that the long side runs parallel with the sofa arm instead of the wall. Would that help to stop it blocking the doorway and resolve the 'not quite right' placement?