There are several strategies that can be used if we have large capital and what you mentioned is one of them. Buying several types of potentially altcoin is a good strategy.

Although we all know that almost all the prices of altcoin will go down when the price of bitcoin goes down and vice versa. If we have a lot of capital, then it would be better not to spend it on one purchase because we also have the opportunity to buy some additional altcoin if the price is lower than the first purchase.