I don’t think anyone else has talked about this but it is heavily implied (in the first seasons anyways) that ash’s type of girl a a feminine girl. Such as when he said (in the Japanese dub) she’s cute, when shown a picture of Giselle who we know is extremely feminine. That is the only factor that makes her“better” than Misty when it comes to looks, even with the beauty and the beach episode, and the bikini. Where he paused and said “it’s weird to see you looking like a girl”. That probably explains why he always acted so nervous around Serena. She is literally his type. But that’s my thoughts on it anyways, anyone is free to like whatever ship they like!
You know what I find interesting about amourshipping? At first they kinda struggled to understand eachother. But overtime throughout the series they kinda learnt each others “language” and it’s really cute. For example on thier first “date”, they could not click at all. However, contrast that to the final eps, where Ash takes her out to the town and Serena agreed to battle. I think a lot of people who don’t like it aren’t usually a fan of vanilla or flustered x oblivious dynamic. That’s totally fine but I am, just my thoughts on the matter. Everyone is free to like whatever ship they like.