Strong, short, feminine, unisex-no frills or popularity. [name_u]Wren[/name_u] is awesome!!! I love that name.
Lately, my favorite one syllables that fit your criteria are:
[name_f]Lark[/name_f], [name_f]Dawn[/name_f], [name_f]Ruth[/name_f], [name_f]Pearl[/name_f], and [name_f]Neve[/name_f]. (neve= short e sound, as apposed to the long e sound =nehv instead of n+eve)
Other options you may like:
[name_u]Quinn[/name_u] or [name_f]Blythe[/name_f]
[name_m]Ace[/name_m] or [name_u]Kyle[/name_u]
[name_u]Kay[/name_u] or [name_u]Jay[/name_u] (blue jay)
[name_f]Jade[/name_f] or [name_u]Rae[/name_u]
[name_u]Chase[/name_u] (ace as a nn) or [name_f]Eve[/name_f]
[name_f]Lux[/name_f] or [name_u]Grey[/name_u]
[name_u]Jude[/name_u], [name_u]June[/name_u], [name_m]Hayes[/name_m], [name_f]Nell[/name_f], [name_f]Greer[/name_f], [name_f]Jill[/name_f], = [name_f]Jillian[/name_f] although not short, can be shortened to [name_m]Ian[/name_m] or Jia(gia)
[name_m]Ian[/name_m], [name_u]Tyler[/name_u], [name_u]Haven[/name_u], [name_u]Skyler[/name_u], [name_u]West[/name_u], [name_f]Noa[/name_f], [name_f]Zara[/name_f], [name_m]Aries[/name_m], [name_f]Gemma[/name_f], [name_u]Luca[/name_u], or [name_f]Ora[/name_f].