Yukimaru Moe does really good Shoujo. There are 4 completed manga's she's done and one still ongoing, but with 10 volumes if you're interested.
(This is my opinion) (^U^)
Hana to Akuma. Moe Kare. Love Monster.
well, this one has season 1 completed, http://www.webtoons.com/id/romance/flawless/list?title_no=595, soo cute
http://www.mangago.zone/read-manga/romanian_gymnastic_society/ (don't be fooled by the ongoing tag, it's completed)
http://www.mangago.zone/read-manga/ssg_meimon_danshikou_keppuuroku/ (this one too is completed, not ongoing)
http://www.mangago.zone/read-manga/pinocchio/
http://www.mangago.zone/read-manga/shinigami_no_ballad/
http://www.mangago.zone/read-manga/tokage_ouji/
http://www.mangago.zone/read-manga/himegimi_no_tsukurikata/
http://www.mangago.zone/read-manga/mekakushi_no_kuni/
http://www.mangago.zone/read-manga/tenjou_no_kajitsu/
http://www.mangago.zone/read-manga/emma/
http://www.mangago.zone/read-manga/karekano/
http://www.mangago.zone/read-manga/my_hero/
http://www.mangago.zone/read-manga/kodomo_no_omocha/
http://www.mangago.zone/read-manga/oujisama_game_kirishima_rira/
http://www.mangago.zone/read-manga/crazy_for_you_shoujo/
http://www.mangago.zone/read-manga/watashi_no_cinderella/
http://www.mangago.zone/read-manga/venus_capriccio/
http://www.mangago.zone/read-manga/wild_damon/
http://www.mangago.zone/read-manga/kitchen_princess/
http://www.mangago.zone/read-manga/marmalade_boy/
http://www.mangago.zone/read-manga/ojousama_no_untenshu/
http://www.mangago.zone/read-manga/mishounen_produce/
http://www.mangago.zone/read-manga/yotteke_otoko_mura/
http://www.mangago.zone/read-manga/eensy_weensy_monster/
http://www.mangago.zone/read-manga/fujoshi_kanojo/
http://www.mangago.zone/read-manga/atsu_atsu_trattoria/
http://www.mangago.zone/read-manga/metto_kun_wa_ikemen_desu/
http://www.mangago.zone/read-manga/futari_no_renai_shoka/
Ik it's a very long list but idk how popular they are. I just know that at the moment, these ones are less popular than e.g. skip beat etc. Hopefully you'll find some you haven't read. These are some of the shoujo mangas that I've read but it doesn't mean that I liked all of them but maybe you'll like them. ;)
I read most of the popular romance mangas so now I'm running short on stuff to read. I would prefer if it is completed because I hate waiting for ongoing series.