From the boys list I absolutely love Reuben. Definitely the best one.
Of the girls, they're all fine but there are none I love. I much prefer Beatrice to Beatrix as it just has a different feel and I think I prefer more serious names - a lot of your girls choices are a bit too cutesy and frilly for me personally. I would probably go for Kitty (with full name Katherine) or Lola myself.
Arlo - I'm not a fan personally. - Arlo Mason, Arlo Kristopher/Christopher, Arlo Zachary, Arlo Ryan, Arlo Sebastian/Sebastien. Florian - I like this one but with Eli it's a little too out there as Eli is more classic. - Florian Issiah, Florian Alexander, Florian Elijah, Florian Theodore/Theo, Florian Owen, Florian Sean/Shawn/Shaun. Reuben - I love this one though. - Reuben Charles, Reuben Myles, Reuben Joseph, Reuben Maxwell, Reuben Samuel. Rudi/Rudy? - No. Only one I know is off Gavin & Stacey and thats a girl. - Rudy Elliott, Rudy Jonah, Rudy Isaac, Rudy Matthew, Rudy Connor.
Beatrix/Betty/Betsy - These are too old-fashioned for my liking and I think the kid might get picked on at school. - Beatrix Eleanor, Beatrix Ava, Beatrix Eva/Eve, Beatrix Grace, Beatrix Claire/Clare. - Betty Jean, Betty Lynn, Betty Ann/Anne, Betty Jane, Betty Jo. - Betsy Pearl Ivy, Betsy Tallulah Ivy, Betsy Emma Jane, Betsy Amber Louise, Betsy Matilda Jane. Clementine - Clementine Louise, Clementine India, Clementine Scarlett, Clementine Lucille/Lucy, Clementine Poppy. Juno - Reminds me of the film Juno. - Juno Avril, Juno Honey, Juno Marie, Juno May, Juno Anne. Kitty - I agree with above I prefer Kitty as a nickname for Katherine. - Kitty Elizabeth, Kitty Paige, Kitty Jade, Kitty Rae, Kitty Jane. I know a Iris Kitty Elizabeth. - Katherine Pearl, Katherine Olivia, Katherine Rose, Katherine Elena, Katherine Louise. Lola - Lola Faith, Lola Rae, Lola Chelsea, Lola Jade, Lola Paige, Lola Mae, Lola Sky/Skye, Lola Juliette. Pearl - Pearl Elizabeth, Pearl Adelaide, Pearl Genevieve, Pearl Madeleine, Pearl Therese/Teresa, Pearl Vivian. Peggy - How about maybe nameing her Margaret and using the nickname Peggy. Margaret Lynn is cute. - Peggy Eleanor, Peggy-Sue Katherine, Peggy-Lou Samantha, Peggy Sophia, Tabitha - Tabitha Marie, Tabitha Grace, Tabitha Anne, Tabitha Sue, Tabitha Rhea, Tabitha Coco, Tabitha Brandie, Tabitha Bethalyn.
Arlo - not keen. Has become a sleb baby name. Also makes me think of Arlo Hyland. Florian - eh, no. Too floral for me. BUT I like Julian, that is a tiny bit floral but less so than Florian. Reuben - love this one. Rudi/Rudy? - I like Rudy, again, it's a bit slebish, but I do like it.
Beatrix - lovely name, the nicknames you plan to use are a bit klunky though. Betty - blah, hotpot Betsy - a little feistier than betty but not attractive Clementine - ugly, too long Juno - ok Kitty - too babyish Lola - too sexual, avoid. Go for Eloise or Louisa and use Lola as a nn. It is already out of fashion tbh Pearl - ok, prefer Hazel, Greta, Lois, Honor, Meryl, Miriam in that vein, old lady names are usually nice, just not the ones you've listed. Peggy - 'eeeez fahhhmleeeeee innneeeee Tabitha - no, it's a cat's name.
Arlo - nice but faddy. Will be very '2013'. Have come across loads lately. Florian - too frilly and 'florid' for me! Plus I associate it with a very 'young fogeyish' German penpal I had in my teens! Reuben - nice. A good mix of not too common/not too strange Rudi/Rudy? - strongly dislike this. I always get stuck on the 'rude' bit, and it doesn't feel like a proper name to me (and Rudolph's not an option imo!)
Beatrix (nn Betty, Bea, Betsy) - nice. Would use 'Bea' as nn. Betty - only as nn for Elizabeth etc. Betsy - ditto Clementine - used to love this (and Clementina) now worry it's a bit too much. Dislike nn Clemmie. Juno - like it, but think this is also very of its time. Kitty - cute as a nn but a bit insubstantial Lola - been done imo. Was very slebby, now a bit old hat Pearl - this is growing on me - like the vintagey feel, but like JennyMackerz I prefer other similar names (Honor, Greta etc). Good as mn. Peggy - Peggy Mitchell, plus it sounds very harsh to me Tabitha - lovely, on my list.
Favourites are definitely Reuben and Tabitha (Tabitha Pearl is nice!)