What's your objection to the tire pressure monitor? Purely cost, or are there functional negatives to it?
I wouldn't say my TPM is fantastic, but it is a handy data point and I'm glad I have it. I admit though I ride K1300S, not an enduro with potential tire adventures.
My biggest issue is that the sensors on the rim can be damaged or accidentally removed if a non-BMW tech is changing out the tires. The way I look at it is that it's a nice thing to have, but it's really something I don't need that can go wrong. I'm used to checking my tire pressure on a pretty regular basis and don't mind continuing to do so.
I wish I could pay the $150 for the chrome exhaust upgrade as I would if I bought the standard GS, but with the GSA I have to get the comfort package (with completely irrelevant naming) for $370 which comes with the TPM as well.
I'm also slightly bitter that BMW raised the GSA price with the options I want $570 from 2014... which is just ridiculous.