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I've done a few where it's tiled behind the pan with a wooden top and white glass (I.e. No green tint) painted on the back. That way you have a nice waterproof surface but you can lift it off, unscrew the wood and get access to the plumbing.
That sounds like a good solution. I don't suppose you have a photo of what the finished article looks like?
pjay-
I do have a picture. In this case the mirror above is mounted on a 2x2 frame as there are some pipes in the corner of the room and the toilet is under a pavement so it's very difficult to chisel into the walls to hide pipes. I like the effect it has of reducing the depth of the shelf above the cistern. The metal flush button is a hans grohe item which is expensive but it helps to set a quality tone. I was asked to leave the toilet unsealed which is why there's a shadow gap.
It's a tiny room so I couldn't get a better angle. Actually the glass looks a bit green here but I have sourced white glass for other places.
Tip for making them is to cut a piece of hardboard to fit the space, check it fits and then take it to the glass supplier. So many mistakes get made by measuring for glass.
Airhead
I've never fitted one offset, it would be an experiment. Usually you use a solid pipe between the cistern and toilet, I guess that's got something to do with the water pressure of the flush. If you changed to flexible it would have to have 2 solid ends to connect to pan and cistern.
I usually pay £80-£100 for a hidden cistern and they are mounted on the wall with a couple of screws, the quality of the internal mechanisms & single or dual flush is probably why I spend more than £50. The expensive frame ones are normally used for pans that hang off the wall with no pedestal.
Having a hidden cistern just means a bit more of a fiddle for maintenance, if possible ensure access to the back of the toilet from a hatch or fit a flexible pan connector so you can connect the pan before pushing it to the wall. Try to at least leave access to the cistern, if it starts to fail you don't want to have to destroy your tiling. I've done a few where it's tiled behind the pan with a wooden top and white glass (I.e. No green tint) painted on the back. That way you have a nice waterproof surface but you can lift it off, unscrew the wood and get access to the plumbing.
Also check that your overflow, which should be internal I.e. Flows into the toilet not a pipe outside can evacuate water as fast as the feed into the toilet. If the inlet valve fails to shut off you don't want water overflowing the cistern. In fact everyone should hold down their ballcock and see if there cistern overflows, it's suprising the number that do.
Apparently flexible flush pipes are a thing, so you can have your offset cistern.