I don't see them making a dukedom based off the name of a house (a structure and not a royal house). Windsor and Buckingham were named for the family (Windsor) and the area (Buckingham) not the palace with the name. Dukedoms also tend to be a larger area of land, like a county.
But a new title, like Duke of Cumbria would be a good idea.
Even if Albany may not be able to be claimed, or may be, there is too much question. Like Windsor, I don't think they will pick a controversial title.
When the Queen made Andrew a duke she copied her father's titles as much as possible: Duke of York [English], Earl of Inverness [Scottish], Baron Killyleagh [Northern Ireland]. Her father had been Baron Killarney, but because Killarney is in the Republic of Ireland, she substituted Killyleagh for Andrew.
When she made William a duke she followed the same format: Duke of Cambridge [English], Earl of Strathearn [Scottish], and Baron Carrickfergus [Northern Ireland].
Maybe she'll use the same template for Harry.
We should be expecting three titles, that has been the pattern for generations. The exception being Edward, but that is because his is temporary. Their titles reflect three of the regions of the kingdom.
either England, Scotland and N Ireland:
William: Cambridge (England), Strathearn (Scotland), Carrickfergus (NI)
Andrew: York (England) Inverness (Scotland) Killyleagh (NI)
DofKent: Kent (England) St Andrews (Scotland) Downpatrick (NI)
DofGloucester: Gloucester (England) Ulster (NI), Culloden (Scotland)
or England, Scotland and Wales:
Philip: Edinburgh (Scotland) Merioneth (Wales) Greenwich (England)
Edward: Wessex (England) Severn (Wales)
Edward will eventually be Duke of Edinburgh, Earl of Wessex, Viscount Severn so like his father a title from all three areas. The other exception with them, instead of his third title being Baron, it is Viscount.
With the exception of Gloucester and Edinburgh, the Irish or welsh titles have been Baron.
Something like Duke of Sussex, Earl of Ross, Baron X (northern irish title) is likely