Silence is golden? Maybe not...

I've decided to insulate above grannies room as well, to stop her complaining its so much colder without her precious mud, I went to get some more fibreglass panels, this time 150mm thickness, also bought another 100mm bale to do the kitchen/bathroom once more to top it up to 200mm total.

Funny story about the insulation, I am buying it from an older man who sells it from a garage in the middle of Kosice, he told me his son is the head importer for Europe for the parent company (Guardian), and that he does this on the side to earn a little bit extra.
His website can be found here: www.izomart.sk
Anyhow, as you can see on the website, it's €1,-/M² per 50mm thickness, so €3,-/M² for 150mm panels.
Funny part is.. It's produced in the USA, shipped over the Atlantic in a container, and then moved all the way to Slovakia, and it's still cheaper than buying Insulation which is made in Europe such as Knauf or Isover, which retails at €2,50/M² for 50mm, and €8,-/M² for 150mm!!!
Bonkers? I'd say so...

I've been doing more and more calculations trying to work out materials, and have come up with three different ideas/plans.

Here's a floorplan for the house, with current door positions, and where we would like to move them roughly (Also bear in mind this is with the walls current.)

 Current

Proposed

Here's the room usages proposed: