It would be presumably be possible to position Alfa as an upmarket-only brand. They are, after all, so well integrated into Fiat that they could cater for the top end of the market while Fiat covers the rest, analagous (to a degree) to Toyota and Lexus.
The missing part from such a strategy is the service dealers. You'd expect Fiat-Alfa dealers all over the place.
If you look at the Fiat network, they have most of the Country fairly well covered, but then look at Jeep and to even more extent Alfa (since there are some standalone Jeep dealers but no standalone Alfa ones) and the picture gets very patchy, particularly in Wales, Scotland, North West England, East Anglia, bits of the South Coast and South West England.
In Wales there are a wealth of Fiat dealers, but not a single Jeep or Alfa sales dealer in the entire Country - your nearest is (South Wales) Bristol, (Mid Wales) Shrewsbury or (North Wales) Chester. In Scotland granted there's loads of Arnold Clark Fiat dealers and some are also Alfa/Jeep, but there are Fiat or Jeep dealers elsewhere in Scotland that have no Alfa (Ian Grieve Jeep, Park's Fiat, Border Cars Jeep/Fiat for example). There's even no Alfa dealer in Edinburgh, yet there's several Fiat dealers and a Maserati dealer there. In North West England there were loads of Fiat dealers but there's a massive gap for Alfa between Mangoletsi Knutsford and Arnold Clark in Leeds now that Blackburn Alfa and Platts Stoke on Trent have closed. Several Fiat dealers have gone as well now, creating gaps there too (Richard Cort Bury, Lookers Stockport, Chorley Group Blackpool), but there's a Maserati dealer in Stockport, who surely could be approached re an Alfa franchise? Failing that why not advertise for dealers like MG, Ssangyong and other brands have done?
It's all hopelessly disjointed. I get that many of the sites will be too small to simply add Alfa in, but this is why Alfa UK need to step up and help financially. I don't know 100% but get the impression from various sources that it's up to the retailers to find the money - they're not going to do that and potentially turf-out another manufacturer on the back of several fancy presentations by the late Sergio Marchionne but not a lot in the way of model launches, are they?
You only have to look at the success Abarth have had in the UK after adding them into large numbers of Fiat dealers. One Abarth is based on the now very old Fiat 500 and the other a much more expensive version of the Mazda MX-5, but they sell because people see them in the dealerships.