It looks perfectly sized to me. Where it's lacking is personal storage space, but if the back wall slides open to provide storage, that's excellent. And the desk area doesn't seem deep enough.
The problem with the big glass wall is that peoples offices tend to be messy. They want lots of desk space to toss crap on. But you want lots of glass so it feels more open (while still giving people quiet work areas). If you can give them good enclosed storage options, then their offices should remain looking relatively neat.
It's got a huge glass wall, how is that claustrophobic? It's far superior to an open floor plan.
I've built out office space for my 40 person engineering group before with individual one person offices. They had doors to shut and most had windows (but not all, all offices have interior space, and space being expensive need to be used), but all had some amount of glass to their hallways. And they all loved them. Apple's Pods are even better than what I was able to get.
You don't seem to understand how hard it is to get any company, even a tech company, to understand the value of one person offices for software development. Most of these decisions are made by operations, essentially the CFO. I was lucky enough to have a CFO who understood lowest cost options weren't always best, that productivity mattered far more.
But even when I convinced him, the building owner pushed back. They give you a certain budget for build-out, but they don't want you building out in a manner that can't be easily sublet if you leave. The building owner felt that larger offices and open space was far more flexible, new tenants would only have to buy cubes!
Apple's Pods seem to be at the forefront of maximizing individual productivity and work satisfaction. I'll bet you can't name any other large company that's made such a large commitment to personal work space.
Note that Louise Mozingo, the urban design professor at UC Berkeley has criticized Apple for the pods, because she thinks that the modern workspace should be an enormous shared space where people can "collaborate" by shouting at each other over their co-workers heads. That's the kind of design advice workspace planners are giving out today.
