Unless you're starting with at least 2 data nodes, there's no reason to start out with 3 masters. The reason is that there is no redundancy of data, so there's no need for redundancy of masters. You can't even spread the load without multiple data nodes, and there would be no replica shards, so your cluster would always be in the yellow state.
Three master nodes is the way to start, but only if you're building a full cluster, which at minimum is 3 master nodes plus at least 2 data nodes. As mentioned, a single data node is not able to form a fully redundant cluster because there's no place for replicas. If you aren't going to have at least 2 data nodes to start, there's no reason to have more than 1 node anyway.