This might be a bit vague question but we are looking for a theme based on bootstrap that works well with large sites that have a lot of different subcategories and product selection.
There are plenty of pretty themes to choose from but most themes doesn't seem to be a practical choice for big sites.
Preferably we want one with not that many backend settings or that need cluttered custom layout inside categories.
We prefer to have the settings done in css and a configuration file in the theme
We need something that is easy for the customers to navigate in.
Right now a boilerplate bootstrap seems to be the way to go and build it up from scratch. But re-inventing the wheel also looks a bit unnecessary.
Example of site we think have a good layout, http://www.kjell.com/
Check this link you will get lots of magento themes.
You can check out good Bootstrap theme for both M2 & 1 on Themeforest: