awww jorge, 'tis lovely when you actually make sense . . .
I don't have enough knowledge of the field to look for bugs. However, the paper has been circulated for a month or so, at least, and was presented at the Monteral scaling conference. So, if there are bugs, they must not be very obvious.
On the other hand, it is hard to foresee all the bad things that could happen in systems that that include human elements. One example of a problem that was not quite foreseen when bitcoin was designed is the extreme concentration of bitcoin mining (with 54% of the hashrate now in the hands three Chinese pools). The protocol becoming the property of a single company was another. The fast price rise (that made the block reward be worth ~$8/tx) was yet another.
So, who knows what failure modes the "NG" blockchain coudl have.
Anyway, I see little chance that the proposal will be implemented in bitcoin. There is already too much software developed out there that assumes the current design. Implementing a change of that magnitude would be like swimming in molasses. Maybe some altcoin will adopt the idea.