It’s worth noting that we’re entering a feature-freeze (see 1.6 (Soft)-Feature Freeze: Nov 8th), but that’s not a reason to hold back from submitting improvements; it just might mean that some things will be merged with a bit of a delay. That said, anything you notice about problems in the upcoming 1.6 are great candidates for getting submitted ASAP.
Thanks in advance for your interest in contributing! Having many eyes on Julia really makes a difference, and newcomers often have a lot to contribute because of their fresh perspective.