[Columbine]

The two that really gave me issue were る and　ろ but the memnonic I used to remember them was that る　has a RUby and in　ろ it's ROlled away.
Similarlyル andレ, though I never figured anything to help remember that.

oh! and vis-a-vis われね I remembered it as わ is like a round mouth saying 'wah' \(oわo)/, れ is like a pair of REins tied to a post waving in the wind, and ね is the spotty NErd left over.