I finished Koi no Chikara and would like to talk about it so spoilers ahead! Suffice to say I enjoyed watching the second time but the series is not a must watch.
Nishimura Masahiko is really good in his role as the sales guy who betrays the stupid Nukui (Tsutsumi Shinichi) but becomes Nukui & Co's greatest ally. He is there to teach the other 3 dreamers the ways of the world and he is the character that keeps everyone connected.
Fukatsu Eri and Tsutsumi Shinichi play the stupid couple who cannot admit that they like it other because of stupid reasons like Fukatsu Eri being too conscious of Yada Akiko's feelings etc. I must admit it did start to get a bit annoying towards the end but they are just so entertaining and have good chemistry. Not Kimutaku Matsu Takako god level chemistry but pretty good.
Yada Akiko is the supporting character who won the audience's support when she told Nukui that it was Fukatsu Eri who get him the job. Of course, she keeps dragging on her one sided relationship with Nukui until the very end and does not want to hear the truth.
Everyone in Koi no Chikara is too nice. That's why the audience supports them and I am surprised I didn't get sick of it. So what didn't work for me in Koi no Chikara? The devil is in the details and the answer is their advertising work.
Nukui and Asada Ryutaro argue all they and all they come up is some ugly photoshop ad. Episode 6 is about some putting some seeds with some balloons. The writer tried to make it seem like such a desperate situation but it was just laughably bad. There are so many ways to make their lives much easier but episode 6 made a mountain out of a molehill.
Basically the details of the advertising work were not as important to the writer in the context of the story but because the details of the work were inadequate it prevented Koi no Chikara from being a must watch show.
I have said this before but Jdoramas like to do shows about stuff like advertising jobs so they can show some person giving a presentation and just say they got the job without showing the day to day blood sweat and tears.
In summary, Koi no Chikara is a fun golden age love story jdorama that doesn't do a good job as a work dorama. The casting and chemistry makes most of it work though. Watchable.