I have an ongoing cloud mining contract with eobot (https://www.eobot.com/user/31196 allows you to "see" my mining) but they also have a pool that I use when I turn on my miners. They are not currently on, but there they have the ability to set it that it mines for 10 minutes on one coin, then switches to another. You can also have it mine for cloud contract, so you would be able to increase your earnings that way, long after the miners are past their prime.