Basically, a light novel series is a collection of novels that have a light-hearted tone, easy-to-read language, and sometimes incorporate elements of fantasy, science fiction, or romance. They're popular among teenagers and young adults.
Well, it can be considered popular. It has a certain following. The world - building in 'ragna crimson light novel' is really appealing, which is one of the reasons for its popularity. Also, the character development is engaging, making readers want to keep reading to see how the characters grow and change throughout the story.
I think Danmachi is good. It offers a unique blend of adventure, magic, and romance. The story keeps you hooked and the characters grow on you as you read. However, like any series, it might not be everyone's cup of tea, but it's worth giving a try.
I'm not aware of any extremely popular 'pharmacy light novel' series off - hand. It's not as common a genre as some others like fantasy or romance light novels.
I'm not sure of any extremely well - known 'dimension light novel' series specifically named that way off the top of my head. However, there are many light novels that involve dimension - hopping or multi - dimensional concepts that are popular, like 'No Game No Life' which has elements of different worlds and rules that could be considered related to dimensions in a way.