I don't disagree, but I think it's important to make the distinction that the OP's argument isn't "replace Bootstrap with your own framework", it's "tweak it so

I don't disagree, but I think it's important to make the distinction that the OP's argument isn't "replace Bootstrap with your own framework", it's "tweak it so it doesn't look like you just drove it off the factory floor". He even gives examples of tools you can use to do so. You don't have to be a designer; just tweak the colors and some of the paddings and you have a very different site. (Hi, thank you guys for letting me monetize my hobby! :D)