I am considering Plusnet and BT. Is there a reason you want to leave BT?
It would be purely financial. The fibre installation by BT was flawless - since then a gang of workmen replaced telegraph poles in the street which caused a fault (loose connection done in pouring rain!) it took two visits to rectify, but in fairness the raising of fault tickets and subsequent action was pretty prompt.
But if there is no Wi-Fi section to the deal with plus net then I'm minded to continue, but I wanted to shake out all the pros and cons to decide.