If the tiles are on top of screed there shouldn't be a huge concern about damaging the pipes as they should be at least 30mm below the surface. As long as whoever removed them takes care not to dig down into the screed you should be ok. Consider leaving the existing adhesive down if it is well stuck, you can use a levelling compound over this to smooth out to them re tile if you have enough space to build the floor up.

dark carpet or carpet that flows. what are peoples thoughts?

I don’t see why not as long as you have a decent underlay. However, may be worth checking with a carpet retailer.

Thank you all! As my carpet is 18mm thick and the tile edge isn't straight I need a bigger Z door bar which are all chunkier. In my second bathroom with the wood effect tiles I cannot find a wood effect door bar to match well and buying online is too hard to tell the shade. The satin nickel one is more subtle which I like as it blends better with the carpet. The chrome one matches better with the bathroom fittings so still very confused :( This new photo is a brushed silver one. which is a bit slimmer than the satin nickel.. Or should I go for shiny chrome like my taps etc? They are fitting part of the carpet tomorrow so I need to make a quick decision and it's driving me mad ;) haha! Thank you This is my bathroom The wood effect ones I have seen look worse with these tiles