Well I just played my 33rd game and drawing the 'Refugee Helper' starting occupation I decided to go bonkers with emigration once and for all, and see how far I could take it. This was a solo play.
Concentrating so heavily on emigration I decided it might be unfeasible to be able to also fill the home board for more income each turn, so my income from the home board stayed at 2 from round 2 until the end of the game (although I decided against doing so in this game, you can actually emigrate on round 1 with the refugee helper card - which is normally impossible).
I tried to boost my income by grabbing Iceland just before it flipped, but didn't do too well - only getting 2 income from it for most of the game and a final income of 3 at the end when I was covering up the -1 spots. I could have probably done better there.
Most of the first half of the game I concentrated on gathering wood and stone in order to get whaling boats and/or housing with ships then emigrating them. In addition I squeezed in a cow and/or sheep when I could so that I would have 3 of each by the last round - which was mostly spent flipping them for the home board coverage. I would emigrate at least one ship every round from round 2 onward, although it was not possible to emigrate on round 6 as my last viking was in the way.
Although I have a longboat at the end of the game this was only due to the occupation card I ended up drawing which allowed me to pay 2 silver and trade in a whaling boat in exchange for a longboat. With so much of my attention devoted to emigration there was no way I would be able to make much of a dent in either Labrador or Newfoundland, so I didn't bother with getting a longboat. In fact I was struggling to get Iceland into the black and only barely managed to do so right at the end of the game before final scoring.
I've found knarrs to be the most useful of the ships in most of my plays and have settled on what I think is an optimal coverage of the home board's forest of negative points - assuming the income will be left at 2, and no pillaging will be done; using the livestock and 3 special tiles - two (the cloakpin and the helmet) coming from a visit to the 'special sale' space and one (the axe) from the crafting space in exchange for an ore, leaving 7 negative spots, which I wasn't able to cover in the end.
It seems obvious that going for an emigration heavy strategy it would be a good idea to get a house or two because you're probably going to end up with a lot of surplus food. It therefore also seemed logical to me to go to the combined build houses/build ships space in column 4 a couple of times to kill 2 birds with the one stone - ships for emigrating and houses to dump the extra food. This seemed to work quite well, and got two of my four occupation cards in play.
In the end I managed to emigrate the maximum number of ships for a total emigration score of 111 points; five knarrs and one longboat. My total positive score was 175 points, with 24 negative points scattered around.
Final score: 151 points:
Emigration seems like a very solid strategy, and if you happen to draw the Refugee Helper as your starting occupation it's possible to get a high score, because you can emigrate more frequently with very limited funds. Consequently it combos quite well with a limited income strategy, and of course helps immensely with the feast each round. Round 6 could hardly have been called a feast - there was only half a bowl of peas served, and in the final round there was no feast at all, because everyone had left.
I've only played twice so far (once solo), and I've done poorly attempting emigration. I appreciate your story here telling how to make it a viable strategy.