4m

This is a band that is gaining in popularity. It is very good when there is Es, but it is also good for inter-G working. I am sure that with reasonable power and FT8 the whole of the British Isles would be in range. The new Yaesu FTX-1F is supposed to include this in European versions.  I would expect 6W and a dipole to reach widely on FT8 especially.

A while back I designed and build a 4m transverter that is on my website. It is only low power but managed to work well. It was in  GQRP SPRAT some years ago.