The Belle Epoque collection can be completed by buying the belle Epoque containers. The containers cost 1k coal in the armory, and give 2 collection items per container. This is the only way to complete the collection now that the event that gave the containers is over. The always courageous collection will likely be able to be completed in the same way, however as the event that gave the collection items was more recent, the containers have not been added to the armory yet. I would expect to see them in around a year. You can earn king of the sea collection elements in each king of the sea season, with 8 items given for each of the past 2 seasons. Pay attention to the news posts about kots, as there are often opt in missions to get items. 2 items have been earned through twitch drops for each of the past 2 seasons as well. On a side note, only specific collections will have the ability to drop items in daily containers. As others have noted, none of the collections you listed can drop items in daily containers, hence why you haven't been receiving any. You can tell which collections will drop items in dailies, as on the collection page, it will have a toggle for collecting if they do drop in the daily containers.
Cant_Think replied to _Marines's topic in General Game DiscussionSo I got really bored this morning, and wrote a simple simulation of buying containers for collection. Assuming you started with 0 items and the exchange rate is 5 duplicates for 1 item, you need to buy on average 28 containers for the collection.