You can't modify the scale of the texture internally displacing the mesh, like you would do with a procedural texture like Noise...
I think one good way to get more details on the waves here is to increase the repeat X Y, and decrease the (spatial) Size...
This will work fine working with tiny waves like you have on your screenshot, but as soon as you are working with big waves, it gets uggly because you immediately spot the repetitive pattern:
To make the ocean feel more realistic you can increase the random amount so you don't have this uggly thing you see above. Although, this will not remove the "pattern" of the water completely, it will just change the way it looks until it's good for you.
An other solution consists in using procedural textures in top of the actual displaced geometry.
We can use textures as normal maps without uv unwrapping the plane because they are procedural, and work with generated uv map.
I'm not going to go into the process of creating ocean textures proceduraly because the community already did this messy work for us. For oceans, I'm using the ocean shader available in the Blendermada addon.
This addon is great if you don't want to get into the mess of creating realistic materials yourself.
Here you can find a link to the download of the addon.
If you don't need the addon and just need the extra waves, here's the ocean material in a blend file. (use Shift+F1 to append and go into the node tree of the blend file to append all of the node groups)
You can experiment with the shader. It's a bit complicated if you go inside it, but if you don't want all of the extra things it provides, you can try to steel some generated normal textures and append them into your original material.
I think the shader looks fine though, here is a simple plane with no displacement. It's unbelievable what you can do with 4 vertices and generated textures:
If you get a grey result, use a hdr environnement texture to light the scene, because by default the light comes at even strength and color from every direction. Your sky texture will do the job as well but you will get less of the glossiness I got in my render.
By combining these two methods you can get some really interesting results.
