I did the fast stream and didn't apply to any other graduate schemes.
The main thing for me is that the others sounded incredibly boring.
Sure I could earn a lot of money but having talked to friends doing other graduate schemes, they just sounded so so dull
I didn't want to audit accounts or be an actuary or advise companies on how to avoid paying tax (these are what many of my friends do)
I really enjoy the combination of intellectual satisfaction and policy making and reactive work/crisis management that you get in the civil service. I love being close to politics. I like that you can move around and try things out.
It does also have good work life balance, great pension etc but mostly it just really interests me
And if you do the fast stream and get promoted, it's not as badly paid as people make out, I make just under 90k which given pension etc is pretty decent money