Countries and territories if not named for a geographic feature or native name tend to be reserved for Royalty. Prime Ministers, Foreign and Colonial secretaries and colonial administrators might get a town, especially an administrative one. (Count up how many Richmonds and Wellingtons there are around the world). A 'discoverer' might be lucky to have a name stick if it lasted long enough before the settlers arrived, as in Tasmania and the Falkland Islands.
As for Native names these were in any case mangled (try pronouncing Madraspattinam in a 17th Century Bristol sailor's accent or Hēunggóng in Charles Elliot's german accented Devon English)
Here's some suggestions
"
Charlotiana"
http://en.wikipedia.org/wiki/Charlotina#cite_note-0"
Charlottina" and "Charlotta". Were all names for proposed colonies varying from Kentucky, through the Ohio valley and Missisippiafter Queen Charlotteof Mecklenburg-Strelitz. (who had enough places and things named after her). For reasons of ease of pronounciation, I suggest
Charlottia for the Ohio district.
Vandalia was also proposed as Charlotte had supposed Vandal ancestry- a suitable name for the annexed area around New Orleans, itself renamed as
New Hanover. The native name of Mississippibeing retained for the teritorry up river.
With the uniting of the Colonies and the need for an independent administrative centre, a new city on the Potomac,
Amhurst, can be imagined.
August and Augusta were common enough names among the Hanoverians and I think that the colony of
Augusta sounds mighty fine and grand enough to belong to a huge swath of the West Coast of North America from the 54th parallel down to the Snake River. One can see the major city of
Francistown receiving mail intended for the re-named
St. Francis Bay
further down the coast in annexed California.
As British North America consolidates, one can imagine the march of soldier's, civil servant's, patron's names and those of their schools Westward.
Wentworth, Bentick, Bathhurst, Brisbane, Prouse, Addington, Butterworth, Popham, Ellingborough, Cradock, Sherbourne, Wellesley, Lancing, Westminster, Rugby, Harrow.
Military victories in other parts of the world would result in 'alien' place names being honoured in new settlements.
Aliwal, Agra, Mysore, Vigo, Salamanca, Carniac,
Finisterre, Navarino.
The problem is that when one has the whole of Oceania, most of Africa AND the Americas, one is going to run out out of names. It would probably end up like any small town where the council name the first new streets after themselves, the next tranche after their wives, the third tranche after their Mother's-in-law and so on.