The downgrade of needed skills to learn a new position or SA is in my opinion a good one.
However, what benefit you'll get from this, the same benefit is also available for your opponent. So, in this case it will be worth to have a young squad in order to learn more positions and/or SA as fast as possible....

we all agreed that 50 points is to much. only with power training it can be worthy, but to spend 50 points on SA and not on the skills for your player will hurt
But to waste tokens on green boosters for power training isn't also worth a 50 point SA/new role!