A good way to increase a maps difficulty is by increasing spacing, If you press Ctrl+A you can see that most of your objects are placed very close to the center. Try to expand more, use edges / corners and increase spacing.
In terms of patterns to use, I usually look to these patterns when I'm blank of ideas:
Standard Patterns (easy to map, works on many songs/parts, basic stuff)
http://imgur.com/a/miPJOAdvanced-ish Patterns (might be a bit more difficult to properly map, dont fit every song/part/intensity, could be used in a wrong way)
http://imgur.com/a/CBSYOKickslider Patterns (idk, in case you like to map (mostly really advanced!) Kicksliders. Red Circles = Suggested next object position)
http://imgur.com/a/7K6CL(Also, you can apply following to most of the examples: The higher the pitch/The stronger the song/The more intense the song gets, the more spacing it has to the other Sliders. If a pattern goes low -> high -> low (spacing), then you could imagine a low pitch sound, a high pitch sound and then a low pitch sound again. You can also change most of the straight Sliders into curved Sliders, if that fits your style/map more)