Why would that be better than sticking with Bootstrap 2? Bootstrap has been a huge boon for us -- provides a cross browser, consistent, and well documented layout framework that has brought valuable organization and unification to our previously hodgepodge and inexpert usage of CSS. It's a fabulous tool, much better than any custom solution we would gin up with the limited time allotted for that sort of thing.
It's not like bootstrap adds 1000 features that can be created manually.