Yeah, that could works, do you mind to share what are those 5 coins? Are the coins btc, eth, ada, xrp, and xlm?
Good altcoins you have choose here, but remember majority of the altcoins have some positive news that why the price keeps going up, more than bitcoin itself. But the question is will the rapid rise will continue? Is 10% enough for you or you might switch your trading strategy and go a bit higher by 15%-20%.?
10% isn't a relatively high number, if you buy €1000 each, then it's €100 profits for each coin, and the 5 coins I mentioned above could increase more than 10% within a few weeks. Just make sure to set the buy and sell arrangement.
That's why I'm asking you why 10% though? Well, it could work, but then again there are a lot of factors you also have to take into consideration. In paper is sounds very simply, but certain parameters could come up that might make you think twice.