This interchange might have been better off using a diverging diamond interchange layout [1]. While not a roundabout they are "magic" and we should use them more often.
They just look confusing because at some point you are effectively driving on the wrong side of the road, but are extremely efficient. My daily commute includes one that cuts a few minutes off what it once took to negotiate the previous traditional interchange.
[1] https://en.wikipedia.org/wiki/Diverging_diamond_interchange