I think you'll find that a 'scape' is very much not a permanent thing. So, working some more plants in (especially to get you started) shouldn't be met with disdain. It will give you good experience with more plants, and having a high biomass in the beginning will help get things started better. Then, later, you can remove many of the plants and go with a more minimal look to match the scape that you want.
I would lean more towards fast growing stem plants, rather than floaters, in the beginning. They soak up nutrients at a prolific rate, and are readily available from many different sources.