So I decided to try to go for this:
(100 + 90*4) * 3.66 = 1683,6 (10 days, 103 quests)
Game is going well so far. I'm lvl 14 at 10AM on day 4, just entered Creiston mines. The plan is to do what I can in the dwarven lands, liberate Bogacho and sign the treaty (!), may be steal what I can in Demonis, then return to the Islands at 6:59 AM on day 5 to finish what I left unfinished there. And that is not much
Left one of the pirate's sons, bartolomeo, puppeteer and ruin guy, as well as several of those pirate ships.