I'm a huge proponent of customisation, but for me, the less I have to see or even think about GRUB, the better.
So there is nothing to fix, the nice choice screen is a feature.
I say it is really nice not to have any problems with the boot process myself.
Ah I take it you don't have ADHD then? For me, it's not the 20 seconds - it's the fact that this time it might be the 2 minutes boot because it did an update in the background. So I'm happy to assume that any boot/reboot is 2 minutes long.