Hi Mark.
The "Snugpack Ionosphere" looks like a useful bit of kit in the same kind of vein and similar design......but more of a tent.....more freedom.
Its only a 3 season shelter.....but with the use of your tarp as well in the Winter weather to block out the wind would help.
Lightweight and compact.......and plenty of space for a matt of some sorts on the floor......easy pitch and pack.
Get the tarp up first if it's raining/snowing and pitch under cover.
Able to store your boots inside as well as other kit.
One of the gripes (there are always a few no matter what) is that there is no mesh pouch to store a light
Would not take much to stitch one on.
Just a thought mate.....well you did ask