I have played around with PyQt5 lately and must say I was very happy.

Reasons for a complete rewrite:

• The code is not very clean, lots of it could be done in a more elegant and extendable way
• The tests are horrible
• Gtk has bugged me quite a bit

Reasons against:

• Lots of work
• Destroys any packages, user configurations, ...

If anybody has an opinion on this, I would love to hear it.