Elowyn - I like [name_f]Elowen[/name_f] (though like most pp I prefer this spelling). It gives off slightly fairytale, mythological vibes while still being down-to-earth. [name_u]Wyn[/name_u] and [name_f]Wynnie[/name_f] are both cute nicknames. Ellies are everywhere at the moment, but it’s a nice nickname, too.
[name_f]Rosalie[/name_f] - I really like [name_f]Rosalie[/name_f] for you. All of the [name_f]Rose[/name_f]- names are familiar but they don’t seem oversaturated yet, and [name_f]Rosalie[/name_f] is one of the sweetest of the bunch. [name_f]Rosie[/name_f] is just the cutest. I would also suggest [name_f]Rosalind[/name_f].
[name_f]Dorothy[/name_f] (nn [name_f]Dottie[/name_f]) - I want to like [name_f]Dorothy[/name_f], but it still feels a bit dusty to me. [name_f]Dottie[/name_f] is cute, though. Would it age well?
[name_f]Melissa[/name_f] (my name is [name_f]Melissa[/name_f], and we would call her MJ) - I don’t mind the idea of naming her after you, especially since it’s personally meaningful, but I don’t love this option. [name_f]Melissa[/name_f] is a nice name with a great meaning, but it seems so different from your other top choices (and MJ is even MORE out of place). I worry that this name just doesn’t seem to suit your style, so I wonder if you would fall out of love with it. Also, were you to have multiple girls, MJ would really stand out and not work well with sister names. I love the idea of [name_f]Melissa[/name_f] as a middle name, or even [name_f]Bee[/name_f] to represent its meaning.
[name_f]Briar[/name_f] - [name_f]Briar[/name_f] always feels slightly masculine to me, but otherwise I’m into it. I prefer the similar [name_f]Bryony[/name_f]/[name_f]Briony[/name_f], which is also a nature name. I agree with pp that it makes an especially good middle name.
[name_f]Adelaide[/name_f] - [name_f]Adelaide[/name_f] is just lovely and lilting, but the popularity of all the [name_f]Addy[/name_f] names does put me off it slightly. I suppose it depends on how popular it is in your area, and how much popularity matters to you. Would you plan to call her [name_f]Addie[/name_f] or by her full name/a different nickname?
Overall, my favorite option for you is [name_f]Rosalie[/name_f], followed by Elowyn or [name_f]Adelaide[/name_f].