Imho there is no reason to make such a drastic redesign.
The existing logo has been around for over ten years and is well-recognised. Throwing it out would hurt the “brand”, would hurt recognisability, more than it helps. You’re throwing out ten years of building logo reputation.
It’s fine to evolve the logo in minor ways, such as flattening it, slightly adjusting the colours, playing with sizing, etc. It has been done before:
These are better ways to modernise the “brand”.
I appreciate your effort, F-Droid lives on voluntary contributions. But this is a bit too drastic.