Ahaha, I love that picture!
But, yes, I understand where you're coming from. Ricken's "I'm a capable adult, shut up!!!" trait is something that is greatly overplayed, and it's frustrating because that's almost all you see of him outside supports. So many of his other, cooler, more interesting personality traits--struggling with the morality of war and combat, his admiration of Chrom and the reasons for it, his pride in and dedication to his family, his insatiable curiosity, how he bases almost his entire view of himself on how others view him, the contrast between his desire to be respected (by Chrom and by others as well) and these childhood pleasures that he still wants to enjoy and cherish, yadda yadda yadda--are just kinda tamped down into supports and hidden by weird stats and incentives to use other mages instead. (He's lucky I'm so biased towards mages that I always use them. Haha!)
And Nowi...oh, Nowi just warms my heart. She's been through so much, and yet she still tries so hard to make people happy. Love that girl! I just love her!
I think that his supports with Lissa, Miriel, Panne, and Henry all do good jobs of displaying his other character traits.
His support with Henry is wonderful! One of my all-time favorites. In addition to the ones I mentioned above, his support with Olivia is also really fun and nice, even if not too substantial. It's just...it's just really cute... (Also, you're right, why doesn't he have a support with Chrom? Their Summer Scramble conversation isn't even really that good, and I feel cheated.)
I'm not particularly savvy on the FE14 supports, but I think a lot of the opposite-sex supports suffer from shoehorned romance. I usually don't pay much attention to S-Supports because they tend to make the support sequence feel dragged-on and less conclusive (or, all the development they make throughout the chain is thrown out the window; See: Nowi & Kellam)--and on the other hand, there are supports that aren't really complete without their S-Support! (See: Henry & Nowi) Sometimes the fact that almost every character supports with every other character of the opposite sex (with certain Chrom/Sumia/Robinsexual exceptions) also puts a damper on things, because some of the pairs just...aren't very compatible, you feel? Whereas the characters of the same sex that they support with are picked out particularly for their character chemistry. Or maybe it's for their stats. I don't know much about stats.