I've always liked the standard chart options and the ease of constructing formulas and setting filters; so much is possible out of the box with a fairly small and simple data model. Even the default layout looks quite beautiful, and then there are all the customisation options. Back when we started using Sisense, this didn't even include Blox -- only regular plugins and those already provide a world of possibilities (the current dearth of community plugins is a real pity -- but that is a different topic)
That said, our data model is far from small and simple and this has caused issues at various points. But none of the other options I investigated had obvious solutions to those issues either.