Repairing/replacing lime plaster on internal walls

[Vector771]

We've removed lining paper in our Victorian terrace to uncover lime plaster as shown in the photo. It's largely intact, but covered in tiny cracks and with numerous areas that feel hollow to the tap (though are clearly sounds enough that they didn't come off with the lining paper). One patch about 20x20cm in the middle top of the picture has come away entirely to expose the brick. From research I've identified two options:

1) Try to repair the lime plaster. Local builder's merchant will make up lime putty so could fill the big hole to near flush then finish with a standard filler. No experience of this and a bit nervous. Presume I'd also need to knock out all the hollow sounding areas... Then use a breathable clay paint.

2) Get rid of the lime plaster, board the wall and get it skimmed. As it's internal I guess dot and dab would be fine as I can't see any bridging issues. People warn against trapping the damp in the wall, but it's been covered in thick lining paper followed by multiple coats of emulsion on each side and seems to be dry (though the lining paper is peeling and plaster is in bad condition...)

I feel a bit out of my depth and the trades I've spoken to don't seem that well versed in lime plaster, so any input appreciated!

 

[StephenStephen]

As an amateur, I find lime putty plaster much easier to use than gypsum. It's slower and more forgiving.
I wonder if professionals are put off because it's slower, and less familiar?

I'd recommend Mike Wye's videos on YouTube, and spend a fiver on a copy of this: https://www.blackdogpress.co.uk/product/lime-in-building-a-practical-guide-by-jane-schofield

Slightly concerned about the builders merchants saying they can 'make up lime putty' - better to just buy a tub of lime putty and make up the plaster as you need it, I'd have thought.
I'm not sure why you'd finish with a 'standard filler'? Why not just make up some topcoat - lime putty mixed with kiln dried (ie; very fine) sand.
You can then, if you wish, water down the putty as limewash as a finish. Takes a few coats, seems like you're painting on water!

Can't see any photo btw