1. What other sort of Germanic groups aside from the Angles, Jutes and Saxons could make it to Britain? Perhaps Frisians, Franks or displaced Alemmanians?
2. What is the possibility and implications of a southern Germanic migration towards the Balkans? Yes, I know the westward movement was account of the Huns (were there any other significant Asian groups that contributed to this migrations, like the Scythians or Slavic groups?) I feel that if you had enough groups crossing the Danube (as opposed to one or two attempting) the Byzantines would do no better at holding back the tide in the long run than the Romans. Less likely, they allow them to settle along the Danube as buffer states to more dangerous groups, kind of like what they did with the goths. I feel that with more potential threats on their borders, they may hold more honorably to their agreement.
3. In addition to the areas of continental Europe that remained Germanic (Scandinavia, Germany, Holland, Austria) what is/are the next (few) most likely areas of permanent Germanic settlement?