How many shards and indexes per node can I have?

I have about 70 million docs in index on a single node.
Does it make any sense to split index on 24 shards if server cpu has 24 cores?
I'm not sure if queries are executed in parallel by many shards on the same node.

Also i think about splitting huge index into smaller indexes (about 50).
One shard per each small index.
So search queries will span 10-12 indexes instead of 50 and i expect they will execute faster.
But is it OK to have many indexes per node? 50 or 100 or 200?


No, because;

Yes they are, even in one shard they are.

How big is huge?