Wow, the graphics are very good... Dont forget of cut off that great empty space in the right side of the map.
One little "problem": 4 of the 3 border countries of South England are with Lands End; the minor continent will be simply a province of South England. The player can hold two continents and have only one frontier, I mean... and get two bonuses. Wales will be a province, too. That Antonine Wall makes South England too easy to hold, for a gigantic continent. And is very easy attack Wales and North England from there, because taking 4 continents you have only 2 borders
In my opinion, South England needs at least one more border with North England, maybe you can then block route between Wiltshire / Sussex.
Lets discuss the bonuses:
(continent - # countries - # border countries - # routes from other conts)
South England: 11 - 4 (3 with Lands End!!) - 3 (bonus: 6, if you change the borders)
North England: 7 - 3 - 4 (bonus: 4)
Lands End: 4 - 1 - 3 (bonus: 2)
Wales: 5 - 2 - 2 (bonus: 2, maybe 3)
Scotland: 8 - 3 - 5 (Can Cumberland attack Borders? I didnt count it... - bonus: 5)
Ireland: 7 - 3 - 3 (bonus: 4)