I am not a designer so perhaps can relate to you question. I think Bootstrap is a great choice for non-designers who basically want to hack a usable and reliable design. Bootstrap has great advantages to designing a site / webapp that is usable and functional. Much of the design has been well vetted for cross browsers and bugs have been fixed to a great degree.
There are lots of resources available as in the comments to customize bootstrap so that it can achieve a reasonable degree of distinction (vs. the default template).
You will find some great themes that you could mimic to almost have no "traditional" bootstrap trace left in the initial UI experience.
Also, once you get used to Bootstrap you are not going to have to relearn the semantics to get your design out. You can focus more on customizations and the core of your webapp.
I've compiled a huge list of Bootstrap resources over the past year (as mentioned in the other comments). I hope to put another "directory" out shortly.