Hi OP,
Ok, yes, if you really hate it just move and suck up the cost. However I don't think things are as chronic as you describe. Old homes are different and once you understand that it's all doable.
Let me walk you through it:
"There is virtually zero insulation and although I’m looking into getting a grant that’s not quick."
Please DO NOT do this. Do some research, this type of activity is resulting in thousands of old homes being write-offs and unsalable. A Victoria home needs to breathe and not be filled with modern materials. This will make it damp, cold and you will have more of an issue than you feel you do now.
Your house shouldn't be cold, so you need to identify if it has been sealed/DPC'd, plastered wrongly and so on. Identify the issue and use appropriate materials it will all be fine.
"Sash windows at front all need replacing. Cheap flimsy ones were out in years ago and all rotten."
Not quite making sense, I am assuming you have wooden sash windows, original or replacement; either way they are almost always repairable by a joiner/sash restorer. Do not go to somebody selling new windows, find somebody that is specialist in this area. It will save thousands and be more appropriate for your home. Also make sure no silicone and so on is used to seal them, as above this will cause damp issues.
You can also get cheaper than chips, magnetic secondary glazing which is proven more effective than standard or heritage double glazing.
"2 of the bedrooms are in the roof space and I isn’t actually a proper room - it’s more of a huge mezzanine and needs work to box it off."
Not urgent from what you say. do this in your own time if you want to in the future.
"There is some damp in the front lobby which concerns me as there is no obvious cause"
Is this on an internal of external wall? things to check are the roof, gutters and ground levels if an external wall. If an internal wall are there any hidden or obvious water /radiator pipes anywhere near. It's almost certainly a leak from somewhere.
Happy to give more specific advice, Just addressing your concerns in this initial post.