Using high resolution monitor with new 12'' Macbook at 60Hz or above

I would like to use the 12'' Macbook with a high resolution monitor (4k preferable, but would settle for 2560x1440).

Here is what I've been able to gather so far:

OPTION 1: Use the digital AV adapter and stuck at 30Hz refresh rate (4K resolution). This is not acceptable for me.

OPTION 2: Buy a USB-C to miniDP / DP adapter. Google supposedly used to sell this, but I can't find it been sold anywhere. This also has the problem of not able to charge while connected to external monitor, which is not acceptable.

OPTION 3: Get a 2560 x 1440 monitor and try to drive it with HDMI at 60Hz. This should be possible in theory since HDMI 1.3 and 1.4 both support it. This is the route I'm considering taking, but not sure if this will actually work or not... Anyone had success with this?

OPTION 4: Get Macbook Pro...

Would appreciate anyone weighing in on this!