I dislike [name_f]Ruth[/name_f] immensely. Sorry. [name_u]June[/name_u] is my choice.
With no context I prefer the name [name_f]Ruth[/name_f] to [name_u]June[/name_u], however with [name_f]Leni[/name_f] I think I like [name_u]June[/name_u] better.
If these really are your only options I would play a little game with yourself to see how you really feel. Pretend you are at the hospital and you need to name the baby. You can’t pick between the two, so you pull one out of a hat - and it is [name_u]June[/name_u]. What is your immediate gut reaction? Are you excited? Relieved? A little disappointed? You can also pretend you pull the other one out, and what are your reactions to that? To make it more realistic you could literally write them down and pull one out, and just be really aware of what your immediate inner reaction is.
Either way they are lovely names and you couldn’t go wrong with either!