The Classical Element: concept art

I really want to draw this animation in photoshop because I am not good at digital drawing therefore it is a good opportunity to challenge myself. Base on the media, I have drawn some fundamental concept art for my animation on photoshop. The quality of the drawings still need to be improve but the sketchy drawings give me rough ideas on the use of colours or styles on the characters.

I am trying to find an appropriate colour for the main character. I noticed that red could catch a lot of  attentions but it could be quite intimidating and it is an angry colour. The other colour that is still eye catching and happy is yellow and I am happy with me choice.

I do not like these concept art because the drawings are too sketchy and I wonder if they will look professional enough as a finish product. I tried different styles of art on the character for example with outline and in various shapes. I feel like they could be developed further more and base on these ideas, I move on to another style of art shown as below.

I am happy with this style of art better than the previous illustrations because I like the graphic design and the hand drawn visual effects. The facial features are simplified that the balloon now have no mouth as it could still express its feelings using only its eyebrows and eyes. Excluding the mouth makes my character unique and less Japanese anime looking which I have been avoiding all the time.

I doubt about the colours. Should yellow be the only bright colour within the balloons or not? I am hoping to gain some opinion from the interim crit.