I also love Rowan and it has been on my girl list for years... I am carrying my second set of twins, due this fall and need to get girl names I like too.
I skimmed most of this thread... Wanted to Add that your Eleanor could be Lenore and short form Nola or Nora.
Laurel is a natural name too. Some writers of blogs I read have unique names for their kids... Finley, Reverie: daydream, Boheme: (re: Bohemian) Gypsy; a person, as an artist or writer who lives and acts free of regard for conventional rules and practices. I like Dakota with Cody as the short version. Elliot, Mackenzie (Kenzie), Lark, Lux. There is Katniss (like hunger games).
I'm struggling too... there are names I love the idea of but can't see giving my child.
My son is Sullivan Archer. His twin was Emmitt Erving. I like older Irish-y sounding surnames and quirky middle names I guess for boys at least... girls I like masculine unisex names that are a little off the beaten path or relate to nature.
I really like Sawyer, and while I prefer it on boys, it does sound really good with Rowan. I absolutely love Rowan (it is my own name after all!).
My favourite unisex name for girls is Emerson, but I'm not sure how well it would go with Rowan with the end sounds being so similar. I don't know why, but today I'm really liking Jericho as a unisex name, you could use Rhee as a nn maybe. I also really like Baize, which I think is pretty and unusual and Circe which is an all time favourite of mine.
I realise I'm basically giving you names that I like, but they can't sound terrible with Rowan or I wouldn't be able to use them either.
I think Mercy, Verena, Fifer and Ottoline might work too.