I agree with you the pillars are unfortunate. The replacement tiles will stand out no matter how close they come to matching so you're better off making sure they are clearly different so the gray one is better. Putting busy mosaic tiles could look nice but will interrupt the flow between rooms which I'm guessing is your problem with the columns in the first place. You will need to create a dextrous solution to tying into the 2x4 wall on the left side but I think it can be done tastefully- maybe beveling it back once you get past he end of that wall.

~$400 including expedited shipping. My GC just had his regular countertop guy do them, which wasn't great.... he had trouble making clean cuts. If I were going to do it again I would have pressed for someone with expertise to cut them. You can see in the image that the facing is not made of the stone peak, because too much was broken during the cutting to make the mitered edge. I'm a little bummed, but mostly pleased with the surface (which is the important part) thus far.

Thanks :) Yeah decided to go with tile. So sand cement is ok over existing tiles if I prep them first? Only problem is, the new pad can only be about 30mm at it's thickest (leaving up to 15mm for tiles) otherwise it'll end up being higher than the hallway floor. So I either need to make the fall shallower or not bother with the waste and make it all level. If I made it level, could I use levelling compound at that thickness or would deck mud/sand cement be the best option? Also, should I be putting in mesh for strength? (I know I should (and will) ask the local hardware what they suggest, but it's great to have suggestions from the Houzz community also)

Thank you so much for the advice. Not sure about black as a colour choice but love navy blue. That would recede but then maybe the greens contrast not so effective? Or dark grey? My roof will be slate grey. Are these free standing mesh panels widely available? The only mesh with which I am familiar as mentioned has to be fixed to the wall or fence. I had thought that the support would need to be freestanding but as my area is also very windy (Lots of Norwesters) I will need to choose carefully from what is available so they are in themslves protected. I have planted jasmine before in Europe but not been successful with an abundance of flowers either in France or Uk, which Is why I didn't list it. However, I am willing to give it another go as the foliage and habit are lovely. Am now going to look up the hedging you mentioned. Was thinking of getting the garden landscaped by someone local to my area but I am sure, like you, they will wonder at the 1.8m restriction! Sadly my subdivision permits only oak trees ( which they removed when subdividing) to be planted which we know grow over 1.8metres. What they hoped to achieve by creating that constraint is beyond me but I am not going to go against it as someone down my road was 'made' to remove their newly planted magnolia trees as they were already over 1.8 when planted. Further I won't live long enough to see an oak tree grow to its prime! TIA of further comment. Kidssiam