Question

Currently you can only draw steps into their grid cells.

However it would be very much appreciated if notes could be 2 steps long, 3 steps long or even span the entire pattern.

You should be able top drag the right edge of a drawn step to adjust its length...

Answer 1

However it would be very much appreciated if notes could be 2 steps long, 3 steps long

This is already possible.  See the resolution steps per row.