I'm with you down to the T... Microsoft is already showing signs of complacency like Apple and their recycled iPhone designs.Upgrade? No. In fact I'm going to jump ship from the SB line.
I bought the i5 256GB dGPU SB in Dec 2015 for around $1800. I've been generally pleased with it (especially typing experience and 3:2 aspect ratio. However, while I do flip my SB around and use it in Stand Mode, I hardly ever use it as a tablet. So I feel like I'm paying extra for something I don't use, and feel that a yoga laptop form factor would work just as well for me.
I had high hopes for the SB2, but it seems that they basically just upgraded the processor and GPU (no form factor changes) in the 13" model, and charging at least $2000 for a 8th gen processor. Therefore I'm seriously giving the hp spectre x360 consideration, especially the 15" model. I get an 8th processor, pen input, yoga form factor and a dGPU that's better than my current SB all for less than $1400.
I will miss the 3:2 aspect ratio though.