Please don’t start more that one thread on the same subject, it just gets confusing when people answer different threads. It is also mentioned in the forum guidelines.
You can always bump your thread up by posting in it, something like, Any ideas anyone.
You need to look at how you want to model this floor, is it just to look at or are you wanting to use it as a a guide to construction.
Looking at the model in a realistic way you may be over thinking the problem.
Take the floor shape without the rake and work how best to fit the 1220 x2440 sheets. Decide where the full sheets start and work from there, it’s only the edges you need work on, the rest are just whole sheets.
Here I have taken the lip and stage left as the square corner and worked out from there. This leave the offcuts at the back where you might get away with leaving them out. Then you have a couple of detailed ones at the front. Mostly this would all be cut square and placed on the raked floor. You may need to cut the lip to fit the extra rake.
You could use various other methods, one being a plugin call Visuhole but it would make ever one of you sheets a unique component. Or solid tools, or Zoro etc, but I still see it as something you need to construct to understand the structure, and when you do you’ll see it’s quite simple.